Wrong. A single interceptor missile cannot intercept multiple MIRVs, but if you launch
multiple interceptors, any number of MIRVs can be stopped.
The problem however lies with the MARVs (Maneuvering re-entry vehicles), which can dodge interceptors.
But here too, multiple interceptors can solve the problem, as an incoming warhead may be able to
dodge 1 or 2 but not more than that.
If the MARVed warhead maneuveres too much, it will lose a fair amount of it's terminal velocity,
making it slow and thus more vulnerable to interception.