Assassinations
According to US policy, 'assassination' of foreign political leaders is illegal and will not be committed by the USA.
As best as I can tell, both under our law and International Law, that refers to deliberately killing foreign persons during time of peace and/or foreign persons from nations whom we are not at war with AND who are not themselves active participants in a conflict. When we are in a state of war and/or armed conflict with a hostile nation/group/force, we can legally target anyone involved with the military (or other combatant) leadership of that nation/group/force, regardless of their presumed military status. For instance, 'civilian' government leaders-- if their job includes responsibility for declaring, continuing, and/or funding warfare (such as legislative bodies often have) or if their job description includes responsibilities such as 'commander-in-chief', minister of defense (etc.) or (even without formal definitions) they are giving orders to their top military commanders, they are legitimate targets for military action in warfare and cannot legally hide behind their designation as 'civilian' heads of government.
(Yes, I'm aware that, following the same train of thought, our President, Congress, etc, are legitimate military targets for enemies of time of war/conflict. True. Our enemies in this conflict, should we manage to screw up badly enough to let any of them get to our civilian government leadership, will almost certainly be guilty of other crimes under the laws of war-- I don't think there's anyone out there who can get an armed force legitimately operating under the laws of war close enough to get a shot. And, 'legal' as an act of war does not mean we let such things happen to our own instead of defend ourselves and prevent it)
As best as I can tell, both under our law and International Law, that refers to deliberately killing foreign persons during time of peace and/or foreign persons from nations whom we are not at war with AND who are not themselves active participants in a conflict. When we are in a state of war and/or armed conflict with a hostile nation/group/force, we can legally target anyone involved with the military (or other combatant) leadership of that nation/group/force, regardless of their presumed military status. For instance, 'civilian' government leaders-- if their job includes responsibility for declaring, continuing, and/or funding warfare (such as legislative bodies often have) or if their job description includes responsibilities such as 'commander-in-chief', minister of defense (etc.) or (even without formal definitions) they are giving orders to their top military commanders, they are legitimate targets for military action in warfare and cannot legally hide behind their designation as 'civilian' heads of government.
(Yes, I'm aware that, following the same train of thought, our President, Congress, etc, are legitimate military targets for enemies of time of war/conflict. True. Our enemies in this conflict, should we manage to screw up badly enough to let any of them get to our civilian government leadership, will almost certainly be guilty of other crimes under the laws of war-- I don't think there's anyone out there who can get an armed force legitimately operating under the laws of war close enough to get a shot. And, 'legal' as an act of war does not mean we let such things happen to our own instead of defend ourselves and prevent it)