If you're trying to kill a nuclear missile in a hardened silo in South Dakota, yes.
If you're trying to hit Chicago (which is where I live), not so much. You set off a nuclear weapon inside the city limits, it makes a mess.
However, the Chicago City Council has outlawed transportation of nuclear weapons inside Chicago city limits, so if the Russians tried, they would be in violation of city ordinances.
Did I mention that Chicago aldermen are idiots?
I think the ICBM's targeting system isn't much different from the one of a ballistic missile.
As for city councils and nuclear weapons I know that it's illegal for an individual to own one in Utah. The mormons may have several wives, an A-bomb'd be good in maintaining peace in such a family :)
Of course, for the countervalue strike you alluded to (e.g. Chicago) a "terror" (or apparent terror attack) attack would be equally effective.