At least two-thirds of all intrastate conflicts active since 1975 have experienced some kind of external support from other states. This support can include the direct participation of military and security personnel but also more indirect forms of aid, such as the provision of intelligence or logistics support, funding, sanctuary or training. Military interventions in the internal conflicts of other states have more than doubled since September 2001, and in recent years the trend has been for increased troop support or ‘boots on the ground’. External support is an essential variable to conflict dynamics: it often makes the conflict deadlier, prolongs the fighting and increases the challenges associated with achieving a negotiated settlement. The evidence also suggests that civilian targeting becomes more prevalent and there is a greater risk that interstate conflicts will be initiated.
Research on external support in civil wars shows how patterns of support have shifted over time. Two contemporary armed conflicts—in Syria and Ukraine—exemplify the argument that civil wars are rarely just internal affairs; they also illustrate radically different kinds of conflict, in part, based on the type of external support they receive.
Syria has been ravaged by a civil war since 2012 that has also served as a proxy battlefield for competing external powers. In 2015 a series of increasingly assertive interventions and counter-interventions by external powers on behalf of their Syrian state and non-state allies or proxies marked a dramatic escalation in third-party intervention. The negotiations over a political settlement to the war provided another forum for this competition. Russia’s military intervention in September 2015 on behalf of the Syrian Government was a major turning point in the conflict but seems unlikely to lead to a final military victory or a stabilizing political resolution. Indeed, it may only push Syria’s conflict in new, unpredictable directions.
The designation ‘civil war’ to describe the conflict in Ukraine is contested precisely because of the nature of the intervention by Russia—the scope of which is itself controversial. A baseline for civil conflict existed in Ukraine in late 2013, but arguably most of the key triggers that transformed a situation of local conflict into violence and war—the appearance of first paramilitary and then military forces, arms and other resources—appear to have been supplied by Russia or by Russian- and Ukrainian-based supporters of the deposed Ukrainian president, Viktor Yanukovych. Western support for the interim Ukrainian Government seems to have had less impact on the conflict. The first meaningful ceasefire and further Russian troop withdrawals from eastern Ukraine in September 2015 coincided with Russia’s Syrian intervention. However, at the end of 2015, with the Minsk II agreement seemingly unravelling, Ukraine’s path to peace internally and with Russia remained uncertain