Nuclear weapons are a good example of IP theft though. Russia stole plans from the US for nuclear weapons to get ahead. The US literally executed people for their role in it.
Why wouldn't they use them? MAD only exists if there is a credible threat. Imagine that you are a leader of a small asian dictatorship with large amounts of starvation. Other countries threaten to invade to dethrone you. If you do nothing, you die.
You're likely to want to use anything you have to keep your power, including threatening to use your nukes if anyone tries anything. That threat is only credible if you are actually willing to do it.
So now we would just have a multitude of countries playing brinksmanship, seeing who can act the most reckless to convince everyone else not to mess with them because "I'll really do it, don't test me". Great, that sounds like a really wonderful world to live in.
