Tanner on Ice — Lawrence Block

Cold War superspy Evan Tanner lost the ability to sleep on a battlefield in Korea. So where the heck has he been since the 70's?
Frozen. Cryogenically. A Tanner-sicle. Which he never thought would happen when he walked into a basement in Union City, New Jersey, more than a quarter century ago. Now he's unthawed and ready to rumble, and his somewhat addled former super secret boss, “the Chief,” is glad his favorite operative's active again.
Tanner awoke to a different world, though some bad things have remained the same … or gotten worse. Even before he can fully acclimate himself to this perplexing future, Tanner's off the Burma (which really isn't Burma anymore) to pose as a monk, destabilize the government, dodge a lethal double-cross, and rescue a beautiful prisoner.
The world's still full of conspiracy, corruption, greed, political chicanery … and beautiful women. So Tanner's back with a vengeance, with a lot of lost time to make up for.