Here is the full list of all 39 IS Defense achievements.
Finish the game
Finish Saint Tropez level
Finish desert level
Survive 20 minutes on the beach
Fire 1000 rockets
Call the helicopter support 30 times
Survive 10 minutes on Saint Tropez
Call the air strike support 40 times
Get all upgrades
Max the support skill branch
Destroy 1000 vehicles
Call infantry support 100 times
Call artillery support 50 times
Survive 10 minutes on the beach
Kill 10 000 terrorists
Finish beach level
Survive 20 minutes on harbor
Destroy 250 Hummers
Max the rockets skill branch
Survive 10 minutes on harbor
Destroy 500 vehicles
Finish harbor level
Destroy planes on the desert level
Max the machine gun branch
Max the player skill branch
Deliver 100 headshots
Destroy 200 vehicles
Kill 3 000 terrorists
Call the cargo support 100 times
Destroy the Scooby mobile
Destroy the fishing boat on beach level
Destroy 100 pontoons
Destroy 100 suiciders before they detonate themselves
Let 100 pontoons land on the shore
Destroy 30 landing crafts
KIll 30 000 terrorists
Survive 10 minutes on the desert
Survive 20 minutes on the desert
Survive 20 minutes on Saint Tropez