Top US diplomats threaten Ankara with consequences for S-400 sale & Brunson case
Experts in Washington say the U.S. State Department still assumes that it will not require sanctions until the S-400s are delivered & activated
Russia and Turkey agree on second batch of S-400 missile systems
Second batch will be delivered in 2021
Turkey seeks firewall to block F-35 fighters leaking data to US
Turkey wants to link its F-35 computer brains to networks that will include Russian systems