I think it is. It hasn't invaded another country since it's revolution. It had defended itself from a US supplied Iraq for nearly a decade.
So then you wouldnt have had any problem selling Hitler nukes. Germany certainly was stable in 1936. Anfd the thought that they may provide terrorists with nujes isnt even in your playbook I suppose.

The current goverment has not been overthrown in nearly 25 years. I would call that stable.
I dont give it much longer.