In my opinion pressure was directed by American deep state war hawks John McCain and Lindsey Graham who were the first to cheer Donald Trump for his belligerent actions. Both McCain and Graham are on record for their insistence of US Military support in arming the terrorist groups in Syria with the goal of removing Syrian President Bashar al-Assad. Both of these war hawks also became hysterical and called for US military intervention when their terrorist proxy armies on the ground began losing to the Russian, Iranian, and Syrian coalition.
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