If Iran could put 200 lb payload into orbit [very small payload] how much payload could be launched for sub-orbital trajectory to California?

With a ballistic missile, it takes (roughly) almost as much energy to hit something on the other side of the planet as it does to get into orbit.

A 200 lb. warhead would be a major development, and not in Iran's future any time soon.

Bowser makes one good point--Iran is not likely to fire an easily-tracked nuclear missile at anyone. The missiles are deterrents. It's the warhead with the serial numbers filed off and shipped somewhere in a box that's going to be the real problem. We already had one proliferation disaster out of Pakistan, and are barely sitting on another one in North Korea.

If an Iranian-built bomb ever does go off in somebody's harbor, you can bet your bottom dollar that the same characters pooh-poohing it now will declare that this development was obvious to everyone at the time, and why didn't anyone do anything to stop it?