Europe, which for nearly eight decades counted the United States as its military guarantor, just received a lesson in the fickleness of American power. Last week, Defense Secretary Pete Hegseth abruptly canceled the deployment of an armored brigade to what the Pentagon often describes as a “model ally,” Poland. The move caught senior members of the Polish government by surprise. Because European officials were never briefed on the change, they were left to speculate about possible motivations: Perhaps the decision was a product of MAGA’s generalized disdain for Europe. Or maybe it was specific payback for Europe’s failure to help with the Trump administration’s war with Iran. The Pentagon’s press office rushed to frame the decision as a carefully calculated modification of America’s force posture in Europe. But that was a harder argument to sell after top Army leaders told Capitol Hill they had learned only days earlier of the decision, which had been made above their heads. Regardless, the Pentagon pressed ahead. Elbridge Colby, the undersecretary of defense for policy, said Thursday on social …