Daniel Wiser reports for the Washington Free Beacon about disturbing developments involving the United States military.

U.S. adversaries including China, Russia, and Iran are developing military capabilities that will allow them to compete with shrinking and aging American forces in the coming years, according to a new report.

The report, authored by the American Enterprise Institute and the Foreign Policy Initiative, warns that U.S. adversaries have been bolstering their militaries and purchasing cheaper weapon systems as the United States cuts its defense budget and delays acquisition of new equipment. Both China and Russia have increased their defense budgets by double digits in recent years, for example, while the United States could reduce its military spending by as much as $1 trillion in a decade under cuts known as sequestration.

“After a procurement holiday in the 1990s and a hollow buildup during the Iraq and Afghanistan wars, American military capabilities have declined independently and relatively to adversaries like China, Russia, and Iran,” the report said.

These adversaries are “closing the technology gap” with the United States, the report added.

The size of the U.S. Navy fleet and the total number of Air Force squadrons have dwindled by more than half since the end of the Cold War. Of the 54 squadrons, less than half are combat ready.

Additionally, several Air Force planes have been in use for more than two decades, including the B-52 long-range bomber, the A-10 Warthog, and the F-15 Eagle fighter jet.

“These older planes are already vulnerable when operating against advanced adversary aircraft and air defense systems such as the Chinese J-20 stealth fighter and the Russian S-400 surface-to-air missile system,” the report said.