On Monday, House Foreign Affairs Committee Chairman Eliot Engel (D-N.Y.) released a letter to National Security Adviser Robert O'Brien expressing his deep concern about "reports that the Trump administration is withdrawing from the Open Skies Treaty" and urging the administration to abandon "such a reckless action."

The treaty, in force since 2002 with 34 nations as signatories, "aims to increase confidence in and transparency of military activities, particularly in Europe, by allowing unarmed aerial observation flights over the entire territory of its participants for information-gathering purposes," the Arms Control Association explains. Specifically, "the Open Skies Treaty allows the United States and our allies and partners in Europe to monitor Russian military deployment," especially in Ukraine, Engels said, and "American withdrawal would only benefit Russia."

It isn't clear that Trump's odd relationship with Russian President Vladimir Putin is behind the prospective switch.

Guys, GUYS. I know today is not the day to say "not everything is a Russian plot," but Trump has no idea what an Open Skies Treaty is, and Putin's not gonna burn chips on an argument over that. There's lots of nutballs loose in this WH; not everything is an order from Moscow. — Tom Nichols (@RadioFreeTom) October 8, 2019 Is it possible that the Russians mentioned dumping Open Skies just to raise some hell in NATO and the EU? Sure. It's more likely that this is the anti-treaty mania that Bolton represented. Bolton and his minions hate treaties, in general. Bolton's gone, but the minions remain. — Tom Nichols (@RadioFreeTom) October 8, 2019

Of course, Russia and former National Security Adviser John Bolton could both want to scrap the treaty.

John Bolton hated Open Skies and started the withdrawal before he was fired. His staff left behind is trying to complete his dismantlement of treaties. US @NATO all support Open Skies. This is Trump and Bolton kicking them in the teeth. — Jon B. Wolfsthal (@JBWolfsthal) October 8, 2019

Engels asked that before Trump burn the treaty, the decision be put through "a transparent process that includes a thorough interagency review and consultation with Congress." Peter Weber