The adjustments to the new threats are wide ranging. Hundreds of desert-tan battle tanks and armored fighting vehicles must be repainted dark green to blend into European terrain. Soldiers accustomed to operating from large, secure bases in Iraq and Afghanistan must now practice using camouflage netting to disguise their positions and dispersing into smaller groups to avoid sophisticated surveillance drones that could direct rocket or missile attacks against personnel or command posts.

American troops no longer have unfettered right of way in the air or priority access on the ground, as they did across Iraqi river valleys and Afghan mountain ranges. In today’s Europe, borders count in all matters military. On a recent Friday, an American Army supply convoy rushing ammunition from Germany to Romania was held up at the Austrian border until the next Monday by restrictions on military convoys during busy summer vacation travel periods.