the funny thing about nukes
Nuclear weapons are pretty much the only weapons you can't actually use and expect to survive the end result.
Nuclear proliferation, or the spread of nuclear weapons across the world and arming nations we'd rather see without nuclear warheads, keeps a lot of people up at night. It should. Out of all the horrifying weapons we've thought of so far, nukes are probably just under biological weapons and right above railguns as far as destructive potential goes. However, nukes come with a catch.
You can build a nuclear weapon and use it for a good, satisfying round of saber rattling, but you can't actually launch one and expect to survive what will happen next. Once you use a nuke on the battlefield, all bets are off and you're doomed.
The MAD doctrine worked for superpowers like the U.S. and the USSR precisely because both of these nations had immense stockpiles of warheads and could both destroy the whole planet in a blaze of mushroom clouds and radiation. Should a nation like Iran get a nuclear weapon, MAD no longer applies.
Many members of the nuclear club are very heavily armed and having spent almost half a century trying to keep nukes in their silos and preventing each other from trying to annihilate major cities and millions of people with a few ICBMs, they won't look too kindly at a newly minted nuke being used by an aggressive state.
One launch of a nuke into a genuine target and one mushroom cloud and it's game over. Every other nuclear nation now has carte blanche to fire off enough warheads to reduce the attacking country to glowing rubble.
Unless you have a stockpile of thousands of nukes manufactured in secret workshops over decades and with at least a megaton yield on detonation, you're an easy target for anyone with a considerable amount of missiles. So it appears that while you can build and stash nukes as political ammo, using them spells certain doom unless you've been making nuclear warheads for a very long time and have a very large territory to absorb a retaliation.
