The U.S. and South Korea have spent almost seven decades honing their preparedness for war. Now fears are growing among the alliance’s proponents that extended peace talks are eroding that advantage.

Defense chiefs from the two nations will gather for an annual meeting in Washington on Wednesday facing a radically changed landscape after President Donald Trump’s decision to restart nuclear negotiations with North Korean leader Kim Jong Un. While those discussions put off the prospect of a conflict, Trump has also canceled major military exercises to facilitate the detente.

Secretary of Defense Jim Mattis and his South Korean counterpart Jeong Kyeong-doo must now find a way to maintain a robust defense without providing regular, real-world simulations for troops that tend to rotate through every couple of years. Trump’s statements calling the exercises “war games” and echoing Kim by calling them “provocative” makes them harder to restart as long as nuclear talks drag on.

“Without the joint military training, there will be an alliance, but a much weaker one,” said Kim Ki-ho, a defense professor at Kyonggi University and a former colonel who oversaw military operation planning at Combined Forces Command. “It’s a North Korea strategy to dissolve the alliance.”

‘Degradation of Readiness’

Even before Trump canceled the so-called Vigilant Ace exercises planned for December, his nominee to lead U.S. Forces Korea acknowledged during Senate confirmation hearings that the freeze had caused a “degradation to the readiness” of forces. “This will be one of my top priorities when I get on the ground,” General Robert Abrams told senators on Sept. 25.

The drills are just one of several challenges to the alliance under Trump’s “America First” policies. He has threatened to withdraw from their two-way trade deal, pressured South Korea to halt oil imports from Iran and tussled with President Moon Jae-in over whether to ease the U.S.’s “maximum pressure” campaign against Kim.

Trump has more openly questioned the value of keeping roughly 28,500 American troops on the Korean Peninsula than any president since Jimmy Carter, saying after meeting with Kim in June that he would “like to bring them back home, but that’s not part of the equation right now.” The administration is pushing South Korea to increase the more than $800 million it pays for the U.S. presence, with the Yonhap News Agency reporting Trump wants Seoul to offset the cost of bombers and aircraft carriers based elsewhere.

Smaller Drills

Mattis and Jeong also were expected to discuss the issue of which side would retain supreme command in the event of a war, a responsibility that has thus far been maintained by the U.S. Seoul has been pushing for greater control, something that could raise political questions in Washington.

Officials on both sides insist the alliance remains “ironclad” and say the troops can maintain readiness, at least in the short-term, through smaller-scale exercises less likely to provoke Kim. Lieutenant Colonel David Eastburn, a Pentagon spokesman, said daily interactions between the two forces demonstrate “not only a strong alliance, but a level of interoperability that’s second-to-none.”

Still, the mass military drills provide troops who speak different languages a rare opportunity to practice the complex maneuvers required in wartime. In the Vigilant Ace exercise, for instance, both air forces had been expected to practice some 700 rapid airstrikes on enemy territory after receiving warning of an imminent attack.

‘Groundless Remark’

Former commanders said the joint exercises were essential to mounting a safe and effective response and blanch at Trump’s criticism of them as “provocative” and “tremendously expensive.” Moreover, suspending the drills means giving up some of the most valuable bargaining chips the allies have in negotiations with North Korea.

“I was stunned,” said retired General Shin Wonsik, who served as the South Korean military’s chief operational strategist. “It was a groundless remark.”

North Korea has for decades objected to the exercises, portraying them as a rehearsal for an invasion to topple the Kim regime. Last December, when hundreds of aircraft, including two dozen stealth jets, flew over the peninsula, North Korean state media accused the allies of bringing the region “to the brink of nuclear war.”

The next question is the fate of next year’s Key Resolve and Foal Eagle exercises, in which allied forces practice war scenarios both through computer simulations and in the field. The spring training has in the past included rehearsing the assassination of the North Korean leader.

“It is useless for the South Korean military to train on its own,” Shin said. “Not doing training means that the South Korean military’s defense readiness becoming terribly low.”