nukes can destroy enemy army without turning whole country into a blasted radioctive wasteland like scaremongers say
That's pretty obvious to anyone with a couple of functioning brain cells. The whole idea of tactical nuclear weapons is limited strikes against military targets. During the Cold War, the NATO doctrine explicitly relied on tactical nukes to stop Russian armored thrusts into Western Europe.
non-proliferation is a lost cause
Non-proliferation isn't based on some third-world politicians being afraid of a nuclear holocaust. It's based on the empirical fact that if you try to develop nukes, Uncle Sam will be very very mean to you.
First, it is not. Idea that this Cold War doctrine was suicidal (for the Europeans) madness is rather popular, I think more than the opposite.
Second, given that exactly zero states were attacked by US for trying to make nukes, I wouldn't call this the most important reason. As for third-world politicians, they adopt the first-word attitude to nukes as thing you can only threaten with but can't really use.
India vs. Pakistan: the nuclear option is dangerously close, and nobody seems to want to prevent it
http://qz.com/541502/a-nuclear-war-between-india-and-pakistan-is-a-very-real-possibility/