Trump has already endorsed the Monroe Doctrine. Now he needs to endorse the Truman Doctrine

Robert Hormats is a Visiting Lecturer at Yale University's School of Management. He served as U.S. Undersecretary of State for Economic Growth, Energy, and the Environment and previously as Vice Chairman of Goldman Sachs International.

It could hardly have escaped notice in the White House, and even more so in the Kremlin, that the Iran War has provided an enormous windfall to Russia — raising oil prices, eliminating sanctions on Russian oil sales, creating new tensions within NATO, and preoccupying American strategic attention and forces.

Lest Putin seize upon these developments as an opportunity to intensify his aggression against Ukraine (which is highly likely given his recent behavior) and feel even more emboldened not to negotiate a constructive outcome, this would be an ideal moment for President Trump to move boldly to disabuse him of such notions.

The president has a fondness for associating himself with “doctrines” of highly regarded predecessors.

President Trump has drawn on and endorsed the Monroe Doctrine — rebranded as the “Donroe Doctrine” — to project American power and influence in our hemisphere. The Donroe Doctrine demonstrated that invoking a historic foreign policy framework — and updating it to contemporary circumstances — can be a force multiplier for American leadership. It rallied domestic support, signaled resolve to adversaries, and provided a clear picture of American intentions in the Western Hemisphere. Europe now needs the same clarity.

That clarity has a name: the Truman Doctrine. Current circumstances in Europe provide the president with not just an opportunity but an urgent need to associate himself with this historic American foreign policy framework as well — one purpose-built for exactly the kind of Russian aggression now unfolding.

Doing so would be a vivid and compelling demonstration that the U.S. is not being diverted by the Iran War from countering Russia’s war of aggression in Ukraine. It would,........

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