The United States is cutting back its deployments in Germany by nearly 12,000 troops and shifting some of those forces around the continent, including relocating some units to Belgium and Italy, Defense Secretary Mark T. Esper announced Wednesday.
About 6,400 troops are set to return to the United States.
The move is certain to rankle European leaders and anger lawmakers on both sides of the aisle who see the American troop presence on the continent, especially in Germany, as a cornerstone of post-World War II order.
“I am confident that the alliance will be all the better and stronger for it,” Mr. Esper told reporters. “We can see some moves begin within weeks.”
The Pentagon’s decision to cut American troops in Germany from roughly 36,000 to about 24,000 is in keeping with President Trump’s idea of “America First” and his deep-seated drive to bring home U.S. forces from wars launched after the attacks of Sept. 11, 2001.
He also has vigorously demanded that European allies carry more of the burden for their own protection. In particular, he has long criticized Germany for being “delinquent” in meeting its commitment to spend 2 percent of its gross domestic product on defense. The plan announced by Mr. Esper on Wednesday will affect American deployments to Germany more than any other NATO ally.
“This is so clearly a punitive move against Germany that its hard to see any benefit from this,” said Rachel Rizzo, the director of programs at the Truman Center for National Policy and who focuses on European security issues. “It really puts future administrations in a bind, it gives them no room to maneuver and will stick in Europeans’ mind well into the future.”
Mr. Trump addressed the issue when he spoke to reporters on Wednesday, stressing that Germany had not paid its full share for defense under NATO commitments.
“Germany is delinquent,” Mr. Trump said.
The outlines of the move, reported earlier in June by The Wall Street Journal, blindsided German officials and some American military officials, who have long seen the U.S. presence in Germany as the bedrock of the American commitment to NATO.
Mr. Esper said the change was a part of an ongoing review of U.S. troop presence around the world that was “accelerated” by Mr. Trump’s announcement to cut forces in Germany. Mr. Esper sought to explain to reporters that the move was not a punitive action prompted by the president.
“I’m telling you that this is going to accomplish what the president said with regard to getting us down to a lower number in Europe, and it meets those other objectives I outlined with the regard to the strategic piece,” Mr. Esper said.
Repositioning the troops will cost “several billion dollars,” Mr. Esper added. The withdrawal and shifting of troops will most likely takes months, if not years.
Roughly 5,600 troops leaving Germany will move elsewhere in Europe, including an F-16 fighter squadron to Italy and an armored unit that will return to the United States and start a rotational deployment in the Black Sea region. The military’s European Command headquarters in Stuttgart, Germany, will move to Mons, Belgium. The Africa Command headquarters, also in Germany, will probably move, although Defense Department officials did not provide a location.
The shift of forces will reduce the Americans’ presence at some U.S. bases in Germany but none are expected to close. The more remote town of Spangdahlem, where the F-16 jet squadron is based, depends on the American presence there and will probably suffer some economic fallout from the withdrawal.
Earlier this month, the governors from the four German states that host U.S. troops sent a letter to more than a dozen U.S. lawmakers pushing them to urge Mr. Trump not to scale back the American troop presence in Germany.
“For decades, Americans and Germans have worked together to build and develop these unique and highly capable structures,” the letter said. “They provide the necessary foundation for a partnership-based contribution to peace in Europe and the world, to which we all share a common commitment.”
In 2012, the Obama administration withdrew two combat brigades from Germany to a mostly muted response, though it was opposed by many officials in Europe.
But that was two years before Russia invaded Crimea and fueled an insurgency in eastern Ukraine with weapons and troops, prompting Europe and American officials to call for a reinvigorated NATO and a harsher stance against Russia.
American bases in Germany span the gamut of missions, from training areas such as the one in Grafenwoehr, to the Landstuhl Regional Medical Center, often one of the first stops for U.S. troops wounded in combat in places such as Iraq or Afghanistan as they return stateside for medical care.
Senator Mitt Romney, Republican of Utah and his party’s former presidential candidate, has called Mr. Trump’s plan to cut troops in Germany “a gift to Russia.” The Kremlin has long seen American troops in Europe as a threat to Russian borders.
Mr. Esper did say that some American forces could increase rotational deployments to the Black Sea region near Russia, as well as to Poland and the Baltic States.
At the height of the Cold War, when military officials planned for armored blitzes through the Fulda Gap, a patch of land in Germany long seen as a flash point for a shooting war with the Soviet Union, the U.S. military had nearly 300,000 troops stationed in Europe.
Melissa Eddy contributed reporting from Berlin.