"Uranium hexflouride centrifuges are not the crucial technology required to creat a deployable nuclear weapon - the real key technology is the advanced mathematics and electronics needed to design and build the thyristors needed to generate critical mass from a small enough amount of Uranium 235. I've not seen any credible claim that Iran has acquired the necessary thyristor technology, nor even got close to it.
Bombing the centrifuges would be about as useful or as logical as bombing aluminium smelting works in Iran, on the grounds that aluminium is a component of a bomb casing."
But the key point is that you can find identify and target a suite of centrifuges. They need a large building, power supplies, and a supply of uranium (which can be tracked remotely).
Also, you don't HAVE to have the special thyristors (I've forgotten the proper name) in a nuclear bomb - there are other ways of initiating the explosion timing. And even if you did need them, thy could be smuggled from China or elsewhere.
The centrifuges would be a large detectable target, loss of which would be critical to the program