Hot Pursuit

Hot pursuit is the chasing of a fleeing enemy across a border into another jurisdiction or territory, continuing an engagement that began on one side of a boundary into the other side. It is both a tactical impulse, the natural desire to keep chasing an enemy who is escaping, and a legal and political problem, since crossing a border in pursuit intrudes on another state's sovereignty and can widen a conflict, so hot pursuit sits at the tense intersection of military necessity and the boundaries that states insist on. The concept applies on land, at sea, and in the air, and in each domain it raises the same fundamental question: when, if ever, is it permissible to follow an enemy across a border to continue the fight.

The tension hot pursuit embodies

The military logic of hot pursuit is straightforward and old, since an enemy who can escape across a border to safety, then return to attack again, is a persistent problem, and the ability to pursue them across the border to destroy them, or the enemy's knowledge that they might be pursued, removes the safe haven that makes their tactics possible. Insurgents and raiders have long exploited borders, attacking from or fleeing to a neighboring territory where the pursuing force could not follow, using the border as a shield, and hot pursuit is the response, denying that shield by continuing the chase across the boundary. But crossing a border, even in pursuit of an enemy, violates the sovereignty of the state whose territory is entered, which is a serious matter that can provoke that state, widen the conflict, and create dangerous escalation, so hot pursuit is fraught with legal and political risk, and states are generally very reluctant to permit their territory to be entered even in pursuit of a common enemy, jealously guarding their borders. This creates the central tension of hot pursuit, between the military value of denying the enemy a cross-border sanctuary and the legal and political dangers of crossing the border to do so, a tension that has no easy resolution and that has produced both formal agreements permitting hot pursuit in some circumstances and serious international incidents when pursuit crossed borders without permission.

Hot pursuit plays out differently in different domains and contexts. At sea, there is an established legal doctrine of hot pursuit in international law, allowing a state's vessels to pursue a ship that has violated its laws from its waters onto the high seas, a recognized right with defined conditions, reflecting the practical need to pursue offenders who would otherwise escape by fleeing to sea. On land, hot pursuit across international borders is far more sensitive and generally requires agreement or risks serious consequences, since entering another nation's territory with military forces is a grave act, and while some neighboring states have agreements permitting limited cross-border pursuit of shared threats like insurgents or smugglers, unauthorized pursuit across a border can provoke conflict. In the air, pursuing enemy aircraft across borders raises similar sovereignty issues. The counterterrorism and counterinsurgency campaigns repeatedly confronted the hot-pursuit problem, since insurgents exploited borders, fleeing to sanctuaries in neighboring countries, and the question of whether and how to pursue them across those borders, or to strike them in their sanctuaries, was a recurring and difficult one, sometimes resolved by agreements, sometimes by cross-border strikes that strained relations with the neighboring states, and always fraught with the tension between the military value of denying sanctuary and the political costs of violating borders.

Why hot pursuit remains a live issue

Hot pursuit remains relevant because the fundamental problem it addresses, an enemy exploiting borders for sanctuary, persists across many conflicts, and the tension it embodies between military necessity and sovereignty has no permanent solution. Wherever an enemy can attack from or flee to a territory the pursuing force cannot enter, the hot-pursuit question arises, and modern conflicts continue to feature it, from insurgents using cross-border sanctuaries to the broader problem of enemies operating from or retreating into territories where pursuit is legally or politically constrained. The rise of long-range strike capabilities added a dimension, since a force that cannot physically pursue an enemy across a border might strike them there from a distance with drones or missiles, which raises the same sovereignty issues in a new form, the cross-border strike rather than the cross-border pursuit, and the extensive use of drone strikes against targets in sanctuaries during the counterterrorism campaigns was, in a sense, hot pursuit conducted by other means, reaching across borders to strike enemies who thought themselves safe, with all the same legal and political controversy. The enduring reality is that borders provide sanctuary to enemies who exploit them, that the desire to pursue and strike those enemies across borders is strong, and that doing so intrudes on sovereignty in ways that carry serious risks, so hot pursuit, whether by physical pursuit or by cross-border strike, remains a genuine dilemma in warfare, balancing the military imperative to deny the enemy a safe haven against the legal and political dangers of crossing the boundaries that states insist on, a balance that each situation resolves differently and that continues to generate difficult decisions and international friction wherever enemies use borders to shield themselves from the forces pursuing them.

Is there a legal right of hot pursuit?

There is a recognized legal right of hot pursuit at sea, established in international law, which allows a coastal state's vessels to pursue a ship that has violated its laws from its waters onto the high seas under defined conditions, a doctrine reflecting the practical need to pursue maritime offenders who would otherwise escape by fleeing beyond the coastal state's waters. On land and in the air, however, there is no comparable general right of hot pursuit across international borders, since entering another state's territory with military forces violates its sovereignty, and such pursuit is generally permissible only with the other state's agreement or in specific circumstances defined by treaty or arrangement between the states involved. Some neighboring states have bilateral agreements permitting limited cross-border pursuit of shared threats, and there are contested legal arguments about pursuit in the context of self-defense against armed attacks launched from a neighboring territory, but these are specific and disputed rather than a clear general right, so unauthorized military pursuit across a land border remains legally fraught and politically dangerous. The essential legal situation, therefore, is that hot pursuit is an established right at sea but not a general right on land, where crossing a border in pursuit requires agreement or risks being an unlawful violation of sovereignty, and the difference reflects the different character of the maritime and land domains, the high seas being an international space where the right of pursuit onto them is recognized, while land territory is sovereign space that another state's forces may not enter without permission, making hot pursuit across land borders a matter of agreement and serious legal and political sensitivity rather than an established right.