Yes, and all of the ones who hold the canonical "keys to the kingdom" in that science are comfortably on the U.S. payroll with frequent handling. This is in keeping with the old saying that idle hands are the devil's playground. We made it our business to see that their hands aren't idle.
Now for the 12 kiloton question...how many former Soviet, ethically challenged bomb designers are there who might be tired of making $50 a week working in a vodka factory?
Find me one. Just one.
Deliver one of those guys to someone who blabbed about the deuterium?! Not a chance! :P