Paul Krugman

Mr. Art of the Deal doesn’t want any deals. He just wants to tear things down.

The institutions Trump is trying to destroy were all created under U.S. leadership in the aftermath of World War II. Those were years of epic statesmanship — the years of the Berlin airlift and the Marshall Plan, in which America showed its true greatness. For having won the war, we chose not to behave like a conqueror, but instead to build the foundations of lasting peace.

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And what Trump is trying to do is undermine that system, making bullying great again.

What’s his motivation? Part of the answer is that anything that weakens the Western alliance helps Vladimir Putin; if Trump isn’t literally a Russian agent, he certainly behaves like one on every possible occasion.

https://www.nytimes.com/2018/07/12/opinion/trump-nato-failure.html