just "American Sniper".

OK, you need to kill everyone in an outpost and then steal a attack helicopter and attack a konvoy after that you need to get to a friendly outpost and land the heli. The last thing is to sneak into a town occupied by enemies, and kill a general/officer in a large tall story building.

is that good enough?

How about a missoin that tasks you with silently infiltrating a compound or base,and having you take a sniping position then having to wait for the target to arive at a confrence or something,and then kill him in the room.

Little late i know.

(ah, plenty of room to write here)
By the design of this mission, I think a logical hardcore rethinking of this mission would be to really dig in the idea of the forward observer role:
- drop the player only with the binoculars, and let him call artillary fire by the map coordinates, not with the point and 0-8-... gameplay;
- Arm him with no optics on the MX, to demotivate sniping. Explosives, sure, if he's really up on the close and personal;
- if the enemy is in hold of an airbase, the player should be inserted via boat. I suppose the skies would be watched and guarded;
- if you say the whole of stratis is in csat hands, where is the artillary fire coming from? instead of land platforms, death could be dealt by gunships, or airstrikes.