Because you can only do it once.
The idea that everyone is just itching to drop nukes is propaganda for the cowardly, but you can only die one time and it doesn't matter how you died once you're dead, so get over it, already.
Discussion
So it would be good to be governed by people who aren't champing at the bit for war then (as I suggested many posts ago)?
That would be the EU.
It's the USA and Russia that need perpetual war, just to not have their economies collapse. Not us.
Given the way the EU is desperate to get involved with the never ending war in Ukraine, one suspects that their system is close to collapse if they don't waste another generation of young people on the battle field. Automation and robotics are going to take a lot of entry level jobs over the next decade and Governments are always worried about what will large quantities of idle people do if the Government can't keep them occupied...