NATO members now talk privately about a Russian attack on one of them as a danger that demands an urgent response, as they grow to doubt that the U.S. will maintain its traditional role of protecting Europe as part of the alliance.

On Friday, U.S. President Joe Biden did his best to rule out the word ‘panic,’ but in tip-toeing around it did more than anyone else to describe Europe’s mood.

"My God,” the president told reporters at the White House, condemning Congress for taking a "two-week vacation” without acting on the package for aid to Ukraine, which has been opposed by Republicans.