Having a bomb and delivering a working bomb to a target are vastly different things. If a country has a bomb, then they have a bomb sitting around somewhere. I

Having a bomb and delivering a working bomb to a target are vastly different things. If a country has a bomb, then they have a bomb sitting around somewhere. It is common knowledge that the nuclear superpowers have a lot of trouble, especially these days, around maintenance and infrastructure. You've got to develop and build good missiles or aircraft to send those bombs out somewhere, and you've got to maintain the whole chain in working order for as long as it takes. They've probably got to stay on high alert 24/7, because you never know when you'll need to press the button and send the bomb to the target. Just building a nuclear bomb without its concomitant delivery system means you'll have to get creative to deliver it. Good luck putting it on on a truck and driving it to the target or something. At that point, you'd rather just have a dirty bomb instead: a lot easier to make, and just deliver it to a convenient highly-populated spot where it'll make a big stink.