NATO’s just-completed summit in The Hague came at a time of extraordinary tension. Since returning to the White House, Donald Trump has repeatedly accused Europe of free riding on U.S. defense spending, raising serious concerns about the health of the Atlantic alliance. His decision to bomb Iran’s nuclear facilities just three days before the summit — in coordination with Israel and without informing America’s NATO allies — has only intensified those fears.

Trump’s strikes against Iran evoked memories of the post-9/11 interventions in Afghanistan and Iraq, when NATO expanded its role beyond addressing conventional military threats to include counter-terrorism operations. While the alliance supported the U.S.-led war in Afghanistan, the invasion of Iraq was far more divisive, owing to the lack of convincing evidence that Saddam Hussein possessed weapons of mass destruction and the absence of an explicit United Nations Security Council mandate. The resulting rift prompted then-U.S. Defense Secretary Donald Rumsfeld to draw a controversial distinction between “Old Europe” and “New Europe.”

But the current situation is even more alarming. Unlike in 2003, when the United States at least made an effort to consult its allies, Trump now keeps them in the dark. He provided no credible evidence to justify the attack on Iran and International Atomic Energy Agency (IAEA) Director-General Rafael Grossi contradicted his claims of an imminent nuclear threat, stating just days earlier that there was no proof of a “systematic” Iranian effort to develop nuclear weapons.