The first three things that crossed my mind:
Kim Jung Un's advisors are telling him to never trust the Americans to stick to an agreement.
Trump is further isolating us from most of our traditional allies. Undoubtedly, serving the Kremlin's long-term goals.
The Iranian agreement was working, and Trump allows his hatred of Obama to be the guiding principle of our country's foreign policy.
edit to add: I think Trump actually wants a war with Iran.
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