The relevant bit here isn't whether it's a weapon or not. It's whether the question has any relevance to space exploration.
The question on how long till the ICBM hits is entirely off topic. It's also not a good question anyway - it has a couple of flawed assumptions, the time given was a rough guide anyway, and simple maths gives you the answer (as does ...
While the question could be cut down to a sub-orbital trajectory question (and closed as a duplicate), that doesn't seem to be what the OP was be asking.
The launch detection, threat assessment and response procedures needed to answer the question are really not on topic.