Which part of reckless deniable proliferation don't you understand?
Who are you going to retaliate against if a smuggled nuke goes off in Tel Aviv tomorrow? Hamas, who delivered it? Iran, who paid for it? North Korea, who supplied the weapon? China, who protected North Korea? Russia, helping them all, and ready with a thousand weapons to scare you off?
Pick your poison, at some point up that chain you stop. Everyone higher up that chain knows you will. They therefore know they can nuke your sorry backside and you'll like it.
Then I assume that you also want to bomb North Korea?