For most of last year, Democrats and Republicans in Congress agreed that the sequester was a defense calamity that would undermine military readiness and break faith with our troops and veterans. It’s hard to watch their prediction come true while the real waste at the Pentagon goes unchecked.

Already this year the sequester grounded a third of U.S. combat aircraft, slashed training for 80 percent of U.S. ground troops, and stranded the USS Harry Truman in port, dropping us to a single carrier in the Persian Gulf. Hundreds of thousands of Defense Department personnel have been furloughed, forcing them away from their duties even as tens of thousands of U.S. servicemen and women are serving under fire overseas. The furloughs even extended to the National Guard, which supports troops in Afghanistan and citizens at home during natural disasters like hurricanes and wildfires. Taken together, these cuts appear to be eroding our military strength from the inside. Secretary Chuck Hagel warned the Senate Armed Services Committee that the cuts could mean “more casualties” in combat and “serious damage to our national security.”

Thankfully we haven’t proved that prediction true yet because we haven’t had to confront a major new military challenge beyond Afghanistan. (Operations there have been exempted from cuts.) Some argue that this demonstrates that these cuts pose no risk. That’s like arguing that it’s OK to drive the family car on loose axles because the wheels haven’t fallen off — yet.

Yet as deep as these cuts go, the sequester fails to address real wasteful spending in the Pentagon. For instance, underperforming and expensive development programs like the F-35 fighter jet are still burning a hole in the Pentagon budget. This new aircraft, which has been shielded from the sequester, is almost a decade behind schedule, expected to cost $1.5 trillion and yet critical systems still don’t work — from the pilot’s “augmented reality” helmet to its 10 million lines of software code. Comparing the F-35’s acceleration, maneuverability and survivability, fighter jet experts have said that the F-35 performs poorer than many legacy aircraft. So even with its problems fixed, the jet’s mediocre performance doesn’t justify its skyrocketing price tag. The other Achilles’ heel of the F-35 is one of its touted features: its stealth capability. The plane’s defenders say that stealth will neutralize the F-35’s other defects and enable it to sneak deep within enemy airspace, hit its targets and escape without ever being detected. The F-35 has even compromised on other capabilities (like carrying fewer weapons) to achieve this stealth capability. But critics point out that adversaries like China and Russia are already developing stealth-beating radars and sensors. If stealth becomes obsolete, so will the F-35, effectively wasting more taxpayer dollars than the entire sequester.

Top Navy officials have warned about the danger of procuring costly new aircraft and ships that depend on built-in technologies, tactics and payloads to be effective. Military technologies are constantly changing and aircraft that can’t change with the times will become obsolete (and therefore incredibly wasteful). Instead of buying thousands of F-35s for the Air Force, Navy and Marines, it would be wiser to invest in updating venerable legacy fighter jets — which have proved their flexibility and effectiveness in combat — with cutting-edge sensors and technologies.

Cutting the F-35 is a perfect example of how Congress can cut military spending yet preserve our military strength. We should be looking carefully for similar opportunities throughout the budget. But however Congress decides to trim military spending, it should not sacrifice the true military fundamentals put at risk by the sequester: maintenance, training and readiness.

Bob Ridder is a former aircraft commander with VMGR-252, MAG-14, 2nd Marine aircraft wing.