Well, nobody is a saint when it comes to the arms trade.
Nations don't have friends, they have interests.
You have a point, however the majority of Russian arms sales head directly to America's worst enemies.
Too true but too many on here are blind to that. All nations in the arms trade (including us) have muck on their hands.
Personally, I have no problem with anti-air defensive installations. They're legitimate national interest purchases. Any nation can make a legitimate case for the purchase of them. THe ones that alarm me are the offensive ones.