Still, I like you completely sidestepped the question of how 'stability' matches up with having a civil war that was one of the bloodiest in history. You're not actually interested in finding the best form of government; you're only interested in defending your own.
Nice attempt to shift the goalposts. Not going to work.
Stability isn't the only goal, but it's an important one.
"Still, I like you completely sidestepped the question of how 'stability' matches up with having a civil war that was one of the bloodiest in history.
Britain had a nasty civil war also.
"You're not actually interested in finding the best form of government; "
No, because I don't believe that there is a "best" form of government. Attempting to immanentize the eschaton usually (always) winds up with a few million people dead.
I'm interested in avoiding forms of government that are demonstrably bad, based on past performance.
Wanting a system of government with proven stability is not a "straw man".
"I assume this means that you think the US system of government is inferior to the UK system of government"
The UK doesn't have PR either. And no, it means nothing of the sort. My argument is that PR tends to be unstable, not that the US system is the only possible stable system.