They have every right to feel threatened and f I was leader of this country and say they did that in Mexico or Cuba, I would feel like my deterent was useless also. There are other motives other than protecting from N. Korea or Iran.
Why Moscow does not Trust Washington on Missile Defense. Towards a Pre-emptive Nuclear War? http://globalresearch.ca/index.php?context=va&aid=27987
Lots of places don't trust the US - due largely to an often somewhat preachy attitude together with a higher level of religious moralism than elsewhere in the West.