Does contemporary armed conflict have ``deep historical roots"?

Does contemporary armed conflict have
“deep historical roots”?
James D. Fearon and David D. Laitin
Stanford University
April 28, 2015
1/41
Motivation
Lots of civil war since end of World War II. The dominant form of
organized political violence.
non
intra
extra
inter
0
5
10
15
20
25
30
35
Types of COW war in current state boundaries, 1816−2008
1816 1827 1838 1849 1860 1871 1882 1893 1904 1915 1926 1937 1948 1959 1970 1981 1992 2003
2/41
Motivation
Asia
N. Africa/Middle East
subSaharan Africa
L. America/Carib.
EEur/FSU
West
World
% country years with
civil war since 1945
26
20
17
8
5
2
14
Note: Fearon-Laitin list. Civil war if ≥ 1000 killed,
≥ 100/yr avg
3/41
Motivation
Plausibly quite large economic impact, outside Asia, West:
avg annual
avg yrs of war
avg total
region
growth hit (%) p value
(if some war) decline (%)
Asia
0.29
0.40
28.5
-9
EEur
-9.74
0.01
6.4
48
LA/Ca
-3.33
0.01
13.0
36
NA/ME
-1.31
0.28
18.9
22
SSA
-2.36
0.03
20.5
39
Note: Avg annual growth hit is coef from regression of WB growth
rates on dummy for civil war, country and region-year FEs (se’s
are clustered by country).
4/41
Motivation
A good number of countries with many years with civil war:
60
50
40
30
20
10
0
% of countries
70
80
90
100
% of countries with at least x years of civil war, 1945−2012
(countries with pop > .5m)
0
10
20
30
40
50
60
total years of civil war
5/41
Questions
I
How much of this persistent warfare post-1945 is a reflection,
or continuation, of a greater tendency for armed conflict in
the same area pre-1945?
I
Does contemporary protracted conflicts have deep historical
roots, as the journalists like to say?
I
If pre-45 or 19th century conflict experience predicts post-45
or post-independence conflict years, why is this?
6/41
Answers, in brief
1. We find some evidence of anti-persistence at the regional level.
I
I
Regions with more conflict pre-45 had less after, regions with
less/moderate amount pre-45 had more after.
Argue that an IR-theory + Tilly-ish story is a plausible
explanation. Violence and arc of state-building.
2. More interesting: Within regions, places that had more
colonial/imperial war pre-45, or in 19th C, have tended to
have more civil war post-1945.
I
I
Will consider a number of possible explanations for this curious
relationship.
But note this is not the sort of persistence invoked by typical
“deep historical roots” arguments (i.e., long lasting ethnic
feuds).
7/41
Outline
1. Why is degree of persistence of armed conflict in particular
places an interesting question?
2. Some “theory,” or reasons you might expect or not expect
long-run persistence.
3. Data.
4. Results.
4.1 Anti-persistence at regional level.
4.2 Pre-45 colonial war → post-45 civil war within regions.
5. Possible explanations for 4.2.
8/41
Why is degree of persistence in armed conflict interesting?
1. Answers could tell us new things about nature and causes of
contemporary conflict, with possible relevance for strategies to
for reducing it.
I
If persistence is very strong, suggests that either
1. highly durable structural factors are important, maybe more
important than changing institutional forms and boundaries of
state system.
2. Or that there is a strong tendency for some conflict to cause
more conflict, not just year to year but epoch to epoch.
9/41
Why is degree of persistence in armed conflict interesting?
2. Journalists, historians, and political scientists often say that
particular conflicts have “deep historical roots.”
I
I
I
Must be true in some sense.
But is it true in the specific sense that current violent conflicts
are just the latest versions of violent conflicts from the distant
past?
Surprisingly, almost no research in IR/Pol Sci on this question.
A tiny bit, very recently, by some economists (Besley and
Reynal-Querol 2014, Voightl¨ander and Voth 2012).
10/41
Why is degree of persistence in armed conflict interesting?
3. Economists keep finding stunning degrees of persistence or
long-run historical impact of things like
I
I
I
I
I
Political institutions (AJR, “extractive” vs “inclusive”)
Plantation economies in new world (Engerman and Sokoloff)
Some economic institutions like slavery (Nunn, Acharya et al
re attitudes)
Culture and democracy (Tabellini, re Europe)
Innovations, like intro of potato or plough (Nunn).
I
Is this also the case for armed conflict? If so, it would be
surprising, at least for political scientists who study conflict.
I
Q is basically unstudied, except for Besley and Reynal-Querol
paper on Africa, who find some conflict persistence from
1400-1700 to 1997-2010 (!)
11/41
Some “theory”
1. Reasons/hypotheses for why armed conflict over last 200 years
might NOT be very persistent in particular places or between
particular groups.
2. Reasons/hypotheses for why armed conflict over last 200 years
might show considerable continuity.
12/41
1. Anti-persistence?
I
Massive change in international system after 1945, and int’l
system/int’l politics conditions the nature and extent of
armed conflict, for the most part.
I
I
Nuclear weapons, effects of Cold War on European integration,
perhaps trade and democracy, essentially eliminate great power
armed conflict (interstate war). Thus Europe (East and West)
saw much armed conflict before 1945 but little after.
In Asia and Africa, colonial era pax gives way to new states in
which ethnic or religious groups that had little or nothing to do
with each other before colonialism or even during, now have
something to fight over: control of new states, or acquisition
of “own” state in UN system.
13/41
1. Anti-persistence?
For example:
I
In Africa, colonizers draw administrative boundaries that
create larger zones of political competition than formerly
existed ⇒ ethnic groups form that didn’t exist as such before,
and start to compete.
I
eg: Kikuyu, Luo, Kalenjin, Luhya in Kenya. Or Yoruba, Hausa
and Ibo in Nigeria. No pre-colonial history of organized conflict
between these groups as such, because they didn’t exist as
such and had nothing to fight over as groups! Conflict was
more local.
14/41
1. Anti-persistence?
I
In sum: Colonizers create largely arbitrary boundaries (an
institution) that then shape political conflict and even the
nature of the parties to it. After decolonization,
1. These new groups have something new to fight over (the
colonial state apparatus), and sometimes they do. Or
2. Groups that control the new states now seek to consolidate
control in peripheries where formerly they had little
engagement and/or that colonial powers left alone (eg, hill
tribes in many S.E. Asia countries).
I
From colonial pax to post-colonial state-building or
state-destroying warfare.
15/41
1. Anti-persistence?
Thus, regions with most conflict before 1945 expected to have least
after, and regions with least before expected to have most after.
1. Tilly (“War made the state and the state made war”) +
Schelling, Waltz, Kant, . . . .
I
Once war (inter and civil) makes relatively strong states in
Europe (and 19th C Latin America to a degree), they are
strong enough to prevent civil war and deter or not care to
fight interstate wars. Related: nuclear weapons, trade,
democracy, EU.
2. By contrast, in Africa, Asia, Middle East, modern state
building process starts later and we are still in violent phase.
I
A possible implication: Will see gradual decline in armed
conflict in these areas as state building proceeds along with
civil and interstate wars.
16/41
2. Persistence?
I
But not difficult to come up with reasons that armed conflict
might be persistent in a locale as well. Two kinds of reasons:
1. Proxy effects: Particular places are persistently conflict-prone
because of durable, “structural” factors that affect conflict
odds in multiple periods of time (e.g., rough terrain).
2. Causal effects: Particular places are conflict prone because
they happen to get wars in the past, and warfare in one time
period itself causes higher odds of warfare in later periods.
17/41
2. Persistence?
Proxy effects: Durable factors cause both pre and post conflict in
particular places.
P1 Valuable territory attracts military competition at all times.
P2 Rough terrain favors insurgents or attracts fierce, anti-state people (Scott
2010).
P3 Certain colonial powers messed things up before, enduring effects.
P4 Greater ethnic diversity in 1800 could have favored more conflict both pre
and post.
P5 Ancient hatreds between communal groups even before 1815?
P6 Maybe some groups already had more martial institutions and traditions
in 1815, and these are persistent.
Causal effects: Conflict in period t causes conflict in period t + 1.
C1 Conflict causes enduring enmities, hatreds.
C2 Conflict destroys institutions that kept/favored peace.
C3 Conflict creates “conflict capital,” martial institutions.
18/41
What we did
I
Coded all COW wars (inter, intra, extra, and non-state) for
“locales,” meaning where there were significant battles
fought. Covers 1815-2007.
I
Used current country boundaries as our “grid” (mainly bec
interested in question of whether there is persistence of
conflict for today’s countries).
I
I
e.g.: We code conflicts occurring within bounds of present-day
Nigeria as in Nigeria even before Nigeria became a British
colony.
Did the same for Peter Brecke’s “Conflict Catalog,” for
1800-2000. Much lower death/conflict threshold, many more
conflicts. Lots more for 19thC Africa.
19/41
Types of conflict
I
COW codes four types, depending on whether one or both
sides are “members of the interstate system” (based on de
jure-ish criteria):
1. interstate: two system members.
2. intrastate: within a system member.
3. extrastate: system member vs non-member. Mainly colonial
and imperial wars.
4. nonstate: non-member vs non-member. e.g., small precolonial
kingdoms, or Latin American republics and Indian princes in
early years.
I
We applied same criteria to code types of conflict for the
Brecke cases.
20/41
Conflict locales in COW and Brecke
war type
# wars
Share in 1 locale
Share in 2 locales
Share in > 2 locales
# locales
intra
334
0.97
0.02
0.01
348
COW wars
extra inter
non
163
94
62
0.92 0.57 0.76
0.06 0.31 0.19
0.02 0.12 0.05
180
238
84
all
653
0.88
0.09
0.03
850
conflict type
# conflicts
Share in 1 locale
Share in 2 locales
Share in > 2 locales
# locales
intra
636
0.92
0.06
0.03
720
Brecke conflicts
extra inter
non
468
215
204
0.83 0.52 0.76
0.13 0.34 0.16
0.04 0.13 0.08
573
463
281
all
1523
0.81
0.13
0.05
2037
21/41
Results
1. “Anti-persistence” at the level of whole regions.
2. Within regions, colonial/imperial wars before predict civil wars
after.
22/41
Results: (1) Anti-persistence at regional level
I
Regions with most conflict before 1945 tended to have least
post-45, and vice-versa
COW data
Brecke data
0.2
EEur
2.5
2.0
1.5
SSA
LA/Ca
1.0
0.8
0.6
0.4
LA/Ca
post−45 inter−, intra−, and non−state conflict yrs/decade
NA/ME
SSA
Asia
0.5
1.0
1.2
NA/ME
0.0
post−45 inter−, intra−, and non−state conflict yrs/decade
Asia
West
West
0.2
0.3
0.4
0.5
0.6
0.7
pre−45 inter−, intra−, and non−state conflict yrs/decade
0.8
1.0
1.2
1.4
1.6
EEur
1.8
2.0
pre−45 inter−, intra−, and non−state conflict yrs/decade
23/41
Results: (1) Anti-persistence at regional level
Theory:
1. War made the state and the state made war.
2. Once war (inter and civil) makes relatively strong states in
Europe (and 19th C Latin America to a degree), they are
strong enough to prevent civil war and deter or not care to
fight interstate wars.
3. In Africa, Asia, Middle East, modern state building process
starts later and we are still in violent phase.
24/41
Results: (2) Within regions, persistence of armed conflict
I
Basic model:
yi,post = α + βyi,pre + X Γ + i ,
where
I
I
I
I
I
I
i is country
yi,t = log(1 + # conflict years in i in period t)
pre = 1816-1945 (or 1815-1913), post = 1946-2000/07
X = covariates.
β = “persistence,” coefficient of interest.
Results same or stronger if use a count model instead of OLS.
25/41
Results: (2) Within regions, persistence of armed conflict
yi,post = α + βyi,pre + X Γ + i ,
I
Questions:
1. Is β > 0 if control only for population in 1800 (and/or land
area) and region dummies?
2. Can we make estimate go to zero if control for possible proxy
effects?
I
I
I
I
I
Soil quality (P1).
Rough terrain (P2).
Colonial power dummies (P3).
Ethnic diversity in 1800 (P4).
Initial income level? Use distance from equator.
26/41
Results: (2) Within regions, persistence of armed conflict
DV = log(all COW post-45 war years +1)
All regions
Asia, Africa, Middle East
0.35∗∗∗ 0.46∗∗∗ 0.27∗∗∗ 0.23∗∗
0.69∗∗∗ 0.71∗∗∗ 0.40∗∗∗ 0.39∗∗
(0.07)
(0.06)
(0.08)
(0.08)
(0.09)
(0.09)
(0.12)
(0.12)
log(pop c. 1800)
0.17∗∗∗ 0.21∗∗∗
0.23∗∗∗ 0.25∗∗
(0.04)
(0.06)
(0.06)
(0.08)
log(land area)
−0.10†
−0.00
(0.06)
(0.08)
log(ruggedness)
0.14∗∗
0.23∗∗
(0.05)
(0.08)
language diversity c. 1800
0.13†
0.03
(0.07)
(0.10)
∗∗
% fertile soil
−0.81
−0.89∗
(0.31)
(0.43)
distance from equator
−0.00
−0.03∗
(0.01)
(0.02)
region fixed effects?
N
Y
Y
Y
N
Y
Y
Y
colonial power fe’s?
N
N
N
Y
N
N
N
Y
N
194
194
194
191
105
105
105
104
adj. R 2
0.12
0.35
0.40
0.46
0.37
0.37
0.44
0.52
Notes: se’s in parens. a log(x + 1); † p < .10; ∗ p < .05; ∗∗ p < .01; ∗∗∗ p < .001
pre45 conflict yearsa
27/41
Results: (2) Within regions, persistence of armed conflict
DV = log(all Brecke post-45 war years +1)
All regions
Asia, Africa, Middle East
0.47∗∗∗ 0.56∗∗∗ 0.38∗∗∗ 0.30∗∗∗ 0.64∗∗∗ 0.66∗∗∗ 0.42∗∗∗ 0.45∗∗∗
(0.07)
(0.06)
(0.07)
(0.08)
(0.09)
(0.09)
(0.11)
(0.11)
log(pop c. 1800)
0.18∗∗∗ 0.29∗∗∗
0.23∗∗
0.26∗∗
(0.05)
(0.07)
(0.07)
(0.09)
log(land area)
−0.10
0.03
(0.06)
(0.09)
log(ruggedness)
0.12∗
0.29∗∗
(0.06)
(0.09)
language diversity c. 1800
0.06
−0.08
(0.08)
(0.11)
% fertile soil
−0.99∗∗
−1.37∗∗
(0.34)
(0.48)
distance from equator
−0.02∗
−0.05∗∗
(0.01)
(0.02)
region fixed effects?
N
Y
Y
Y
N
Y
Y
Y
colonial power fe’s?
N
N
N
Y
N
N
N
Y
N
194
194
194
191
105
105
105
104
adj. R 2
0.20
0.44
0.47
0.53
0.34
0.37
0.43
0.54
a
†
∗
∗∗
∗∗∗
Notes: se’s in parens. log(x + 1); p < .10; p < .05;
p < .01;
p < .001
pre45 conflict yearsa
28/41
Results: (2) Within regions, persistence of armed conflict
Doubling pre-45 conflict years in a territory associates with a
30-40% increase in post-45 war years in the Africa, Asia, Middle
East regions.
29/41
Variants, robustness: Region by region.
2
6
19
54
147
Argen
Brazi
Hondu
Mexic
402
Antig
St.
K
Domin
Beliz
Guyan
Surin
St.
VL
St.
Barba
Trini
Baham
0
Urugu
Jamai
2
6
19
54
19
Azerb
6
Georg
Roman
CroatBosni
Ukrai
Russi
54
147
Yugos
Tajik
Kosov
2
54
19
Peru
El Sa
Grena
0
San M Irela
Belgi Switz Italy
Swede
Norwa
Denma
Austr
Monac Austr
Franc
Finla
Malta Canad
Luxem
New Z
Germa
Liech
Andor
Icela
0
Germa
Spain
Portu
Brecke war years post 1945
2
Nethe
Parag
Domin Cuba
EcuadBoliv
Chile
Costa
Panam
Haiti
Slova
Hunga
Moldo
SloveCzech
0
Greec
Colom Guate
Nicar
Venez
6
19
6
Unite
EEur
2
Brecke war years post 1945
54
LA/Ca
Unite
0
Brecke war years post 1945
West
402
Czech
0
2
Kyrgy
MonteBulga
Polan
Turkm Eston
Maced
Lithu Alban Kazak
Belar
LatviArmen
Uzbek
6
19
54
Brecke war years pre 1945
Brecke war years pre 1945
Brecke war years pre 1945
NA/ME
SSA
Asia
147
402
2
Libya
0
2
6
19
54
Brecke war years pre 1945
147
402
Mauri
Gabon
Comor
Mauri
Zanzi
Seych
Sao
T
Cape
0
Burki
Botsw
Togo
Gambi
Centr
2
Madag
Zambi
Seneg
Lesot
Guine
Ghana
Malaw
Mali
Swazi Ivory
6
19
Benin
54
Brecke war years pre 1945
147
402
54
Bangl
Sri L
19
6
54
Tanza
0
Unite
Bahra
Qatar
Yemen
Yemen
Niger
Djibo
CamboPhili
Thail
Vietn
Laos Myanm
Indon
Pakis
Malay
China
Afgha
Singa
EastPapua
2
Jorda
Brecke war years post 1945
Tunis
Saudi
Guine
Sierr
KenyaNiger
Rwand
Equat
CongoCamer
Liber
Nepal
South
North
Brune
Maldi
0
6
Cypru
Kuwai
Burun
Namib
Zimba Democ South
19
Moroc
Alger
Syria
Turke
Egypt
Eritr
Ugand
Angol
Somal
Chad
Mozam
Sudan
6
Iran
2
19
Leban
Ethio
South
Israe
Brecke war years post 1945
54
Oman
0
Brecke war years post 1945
India
Iraq
Yemen
Taiwa
Vanua
Tonga
Fiji Bhuta
Tuval
Repub
0
2
Marsh
Nauru
Solom
Palau
Kirib
Mongo
Samoa
Feder
6
Japan
19
54
147
402
Brecke war years pre 1945
30/41
Variants, robustness
1. Results same or stronger if pre = 1815-1913 or post = max{1945,
year indep}. → not about continuation of specific conflicts
immediately before/after 1945.
2. Results very similar if use post-45 (“post-treatment”) measures for
population, ELF, per capita income, avg Polity score. → suggests
that these are not pathways for a causal effect, if any.
3. Not much change in estimated β if add many more covariates:
Natural resource measures, relig frac, % muslim in 1900, climate
variables, landlocked.
I
I
(using Altonji et al logic) Omitted variables would have to be at
least twice as related to pre and post conflict as measured
covariates to make β = 0. Much larger if use main controls
measured “pre treatment” with full sample.
Suggests some of the estimated effect is probably causal rather than
entirely due to omitted proxies.
31/41
Types of conflict and persistence
Most of the action is in relationship between colonial and
imperial war before 1945 and civil war after 1945.
32/41
Results: (3) Colonial/imperial war pre and civil war post
DV is logged post-45 civil conflict years (plus 1)
COW
COW
Brecke
pre45 interstate conflict years
−0.14
−0.10
−0.14
(0.11)
(0.11)
(0.12)
pre45 civil conflict years
−0.02
−0.09
0.07
(0.10)
(0.10)
(0.09)
pre45 extra-state conflict years
0.24∗∗
0.21∗
0.24∗∗
(0.09)
(0.09)
(0.08)
pre45 non-state conflict years
0.26∗
0.22∗
0.17∗
(0.10)
(0.11)
(0.09)
region fe’s
Y
Y
Y
log(pop) c. 1800
Y
Y
Y
colonial power fe’s
N
Y
N
other controls
N
Y
N
N
194
191
194
adj. R 2
0.32
0.38
0.34
Brecke
−0.14
(0.12)
−0.01
(0.09)
0.19∗
(0.08)
0.10
(0.09)
Y
Y
Y
Y
191
0.42
Notes: Pre-45 conflict years are all log x + 1. se’s in parens. † significant at
p < .10; ∗ p < .05; ∗∗ p < .01; ∗∗∗ p < .001
33/41
Why would colonial war in 19th C predict civil war after
independence?
Recall, two types of explanations:
1. pre-45 conflict has a causal effect on post-45 conflict.
C1 Conflict causes enduring enmities, hatreds.
C2 Conflict destroys institutions that kept/favored peace.
C3 Conflict creates “conflict capital” or martial institutions.
2. Proxy effects: Durable factors cause both pre and post conflict in
particular places.
P1 Valuable territory attracts military competition at all times.
P2 Rough terrain favors insurgents or attracts fierce, anti-state people
(Scott 2010).
P3 Certain colonial powers messed things up before, enduring effects.
P4 Greater ethnic diversity in 1800 could have favored more conflict
both pre and post.
P5 Ancient hatreds between communal groups even before 1815?
P6 Maybe some groups already had more martial institutions and
traditions in 1815, and these are persistent.
34/41
Why would colonial war in 19th C predict civil war after
independence?
I
We controlled for valuable territory (P1), rough terrain (P2),
colonial powers (P3), ethnic diversity (P4), initial income/dist
from equator. See little or no change in persistence estimates.
I
Suggests at least a portion, possibly large, of effect is causal
rather than due to unmeasured, omitted variables.
I
That is, maybe random things w/r/t post-45 conflict
determined placement of pre-45 colonial wars, and the
conflicts themselves then (somehow) caused increased risk of
civil war post-independence.
35/41
Why would colonial war in 19th C predict civil war after
independence?
I
Not ethnic feuds causing enduring enmities (C1, P5). Not the
type of conflict persistence we observe, and . . .
I
For subSaharan Africa and Asia we have coded “Side A” and
“Side B” in COW wars (not interstate) and find only four
cases of ‘same’ ethnic groups fighting each other before and
after 1945 (out of 165 conflicts).
I
Might be more if use lower-threshold Brecke conflicts (will
try), but very unlikely to account for more than a very small
share of the persistence we observe.
36/41
Why would colonial war in 19th C predict civil war after
independence?
Another proxy effect possibility: Pre-colonial state structures →
persistence?
I
Maybe colonizers tended to fight with locals where locals had
more developed state structures and then either
1. these structures survive post-independence and are used in
attempts to “rationalize” modern states in new, formal
boundaries (e.g., Burma). Or
2. colonial wars destroy state structures that might kept peace or
developed more effectively (e.g., Sudan).
I
We use Putterman et al’s measure of precolonial state
structures.
37/41
Why would colonial war in 19th C predict civil war after
independence?
Dep. var.
state structures, 1701-1850
state structures, 1701-1850
N
Region fe’s
Pop and land area
All other controls
Africa, Asia, Middle East only
COW data
extrastate, pre45 civil war, post45
0.11
0.21
-0.09
(0.44)
(0.50)
(0.60)
0.54
(0.49)
76
Y
Y
N
Brecke data
0.92†
(0.55)
76
Y
Y
Y
-0.41
(0.70)
76
Y
Y
Y
38/41
Why would colonial war in 19th C predict civil war after
independence?
What’s left?
I
Somewhat by process of elimination, evidence seems most
consistent with a “conflict capital” or “martial institutions”
hypothesis (C3 or P6).
I
Conflict in one period encourages development of culture or
institutions that favor conflict later on. Could have happened
both in 19th C with colonial/imperial wars (C3), and/or
before (P5).
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Why would colonial war in 19th C predict civil war after
independence?
Evidence:
1. 18th C COW conflicts among locals in Africa, Asia, Middle East
predict, somewhat, colonial/imperial war in 19th C. However, not
significant as predictors for post45 civil war.
2. Groups that fought colonizers often appear post-45 fighting with
other groups in new state. For example:
2.1 Group fights colonizers in 19thC then minorities in new state
post-45:
I
Han, Burmese, northern Arabs (Sudan), Xhosa, Sinhalas (Sri
Lanka), Christian Malays (Philippines), Javanese, Amhara, Mbundu
(Angola), Turks, Hausa-Fulani, Darods (Somalia).
2.2 Group fights colonizers in 19thC then for autonomy vs group that
dominates post-colonial state:
I
Kashmiris and Sikhs (India), Pashtuns (Pakistan), Zulus, Moros
(Philippines), Palestinians, Tigreans (Ethiopia and Eritrea),
Acehnese, Tibetans.
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Summary
1. Some evidence of “anti-persistence” at regional level, consistent with
Tilly’s famous arguments supplemented by some IR theories about
deterrence, democracy, nuclear weapons, etc.
2. More interesting and novel: Within regions and in particular in the
regions that were mainly colonies in 19th century, colonial/imperial wars
in 19th century or 1815-1945 associate with civil war post-1945.
3. Apart from population of territory, this persistence effect does not
diminish much at all if control for measurable durable influences on armed
conflict. Suggests that some part of this likely to be a causal effect.
4. Hard to say, but evidence most consistent with idea that conflict leads to
development of martial cultures or institutions in particular groups that
are quite persistent.
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