Today marks the 65th birthday of the United States Air Force.

Since 1947, the Air Force has served the U.S. as the dominant air power in the world. With thousands of years and miles of service among the airmen and amazing successes such as the SR-71 program and the no-fly zone over Libya in 2011, the service has much to be proud of.

However, a few other recent milestones make this celebration somewhat bittersweet. Nearly as old as the service is the B-52 strategic bomber fleet, which recently celebrated its 60th birthday. While the bomber fleet has successfully deterred nuclear action and flown conventional missions alike for more than half a century, these aircraft represent a greater trend that the Air Force and U.S. military in general have accepted: using increasingly old equipment to perform missions. Congress needs to take steps to ensure that this fleet is modernized and that the Air Force develops a legitimate replacement.

Another recent milestone occurred in 2008, when a pilot flew the same F-15 that his father had flown 30 years before. As with B-52s, the F-15 Eagles have performed numerous successful missions and have been critical to national security over the years. These aircraft have been pushed beyond their intended thresholds—perhaps even more so than the bombers. F-15s were originally to last 4,000 flight hours, but due to increases in demand and lack of replacement, their service life was doubled.

The replacement for the F-15—in fact, the replacement for the F-16, A-10, F-18, and the AV-8B Harrier as well—is the F-35 Joint Strike Fighter. The U.S. Air Force has staked its future on this aircraft, yet President Obama’s budget will significantly reduce the number the government will obtain. This decision, as is the case with many of Obama’s reductions to national security, was made merely to cut spending for fiscal reasons without genuine consideration of current or future threats. Congress should fund the fighter fleet of the future at robust levels.

Since 1947, the U.S. has remained the most dominant air power in the world. The nation is now at a turning point. If Congress does not reverse the Administration’s reductions, America’s air power will be in jeopardy. National security relies on our forces’ continued capability on the ground, at sea, in the air, in space, and in cyberspace. We cannot afford to let any of these forces fade away.