he's giving the US a very strong motivation to stop him from making future leaks
No, he's not. There's others that have the informations to release upon his death, etc.
Snowden would like to introduce you to his 900 pound pet gorilla named DeathMonkey.
Please beware, the gorilla is rather irritated, protective and bites.
CowTip: DeathMonkey is his dead man's switch.