I suspect there are 4 primary issues here: 1 - It commercially benefits the Russians, not a western company based in a NATO country or it's allies. read more
If Greece and Turkey has military conflict then the Greek missiles and fighters attacking Turkey could not be targeted with the US Patriot missiles since Greece is part of NATO. So the Patriot System could be useless for Turkey which faces multiple threats that US does not share. read more
I can’t answer if Russia would be willing to sell S-400 missiles to Turkey. However such a deal would be a waste of Turkish taxpayer money, because you would want all your weapon systems to work together for maximum efficiency and S-400 missile systems are incompatible with NATO radar systems for obvious reasons. read more
The existence of Russian S-400 missiles on Turkish soil has annoyed the US. Chairman of the US Joint Chiefs of Staff General Joseph Dunford said that Turkey's possible purchase of Russian S-400 missile defence systems is "concerning." "Turkey has not completed a deal with Russia yet. read more