That being said, the current defense contractor driven hysteria over Turkey buying the S-400 SAM system from Russia is not one of those reasons:
The most sophisticated fighter jet in the world, the F-35 Joint Strike Fighter, will play a smaller role in the future of European security than originally conceived. On Monday, the Senate amended its version of the 2019 defense authorization act to block the sale of the fifth-generation fighter jet to Turkey. The reason: the NATO ally’s purchase of the Russian S-400, a radar and missile battery with a lethal range of 250 km. In routine operation, the sensor- and transmitter-packed jet exchanges electronic data with friendly anti-air systems and sensors, and if Turkey were to do this, data collected by the Russian-built weapon might find its way back to Moscow.The S-400 is arguably the best SAM system currently deployed, and as noted above, it scares the crap out of the US military.
The House version of the bill also expresses concerns about the S-400 and Turkey and requires a report 60 days after the bill’s enactment to assess Turkey’s purchase of the system and possible consequences to U.S. aircraft.
Turkey inked the S-400 deal last year, over strenuous objections from the U.S. and other NATO-member governments concerned about an ally using Russian air defense systems. “A NATO-interoperable missile defense system remains the best option to defend Turkey from the full range of threats in the region,” Pentagon spokesperson Johnny Michael told CNBC last fall.
Turkey’s Prime Minister Binali Yildirim called Monday’s decision “lamentable.” It’s also very inconvenient for Turkey’s political elite, coming just days before Turkish elections.
The U.S. military has gotten up close and personal with the S-400 over Syria, where the Russian military has deployed to aid the Assad regime. Its deadly presence reshaped how the U.S.-led coalition flies air ops, Lt. Gen. Jeffrey Harrigan told reporters in September. “‘We are consistently monitoring them to see if something changes their intent because we have to manage that and respond quickly…We look at it every day. It’s an everyday discussion to make sure our force can manage that risk.”
Its detection range, which almost certainly exceeds 500 km, means that installations in Kaliningrad will be getting all the data that the Russians could ever want on the F-35.
It would cover all of Poland and the Baltics, going as far west as Berlin and Copenhagen, and that doesn't include coverage from installations in Belarus.
This is about defense contractors not getting their vigorish from a NATO ally, nothing more.