David A. Andelman, visiting scholar at the Center on National Security at Fordham Law School and director of its Red Lines Project, writes for CNN Opinion, where his columns won the Deadline Club opinion writing award. Author of "A Shattered Peace: Versailles 1919 and the Price We Pay Today," he was formerly a foreign correspondent for The New York Times and CBS News. Follow him @DavidAndelman. The views expressed in this commentary are his own; view more opinion at CNN.

(CNN) There is a belief, only reinforced after his speech to the United Nations on Tuesday, that President Donald Trump is positioning the globe for hurtling toward nuclear proliferation, courting disaster.

Trump's defiant messaging -- given Iran's steadfast adherence to a nuclear deal that the United States wants desperately to kill -- is powerful evidence of looming troubles.

Playing to an American audience and voters in the November midterm elections, Trump began his half-hour speech to the UN General Assembly by boasting about the accomplishments of his presidency.

Enunciating the theme of many of his private conversations with world leaders on the UN's sidelines, Trump said the theme of this week is sovereignty: "standing up for America and the American people."

Indeed, Trump was not to be denied the limelight. Though the UN pointedly observes "Delegations are reminded that statements should not exceed four minutes," Trump rambled on for more than a half hour.

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