While Congress debates cutting Social Security, the most expensive weapons program in history — with an estimated lifetime cost of $1.5 trillion — is making questionable progress.

The US Marine Corps recently announced that, after 14 years of development, the F-35 is ready to be deployed and issued a declaration of initial operating capability (IOC). The IOC means that, in theory, the F-35 is fully operational and ready for combat use.

But while the Marines now officially can use the F-35 in combat, experts continue to question whether they should. The F-35 still has a host of reported problems that could endanger pilots and other US service members in a combat zone.

Though the IOC for the F-35b comes four years late, the plane will still not have a functional Gatling gun to protect ground troops until 2019. The Marines themselves have admitted that the plane’s sensor, communication, and night vision systems are also not up to the standards they set.

A report [PDF] from the Department of Defense’s Director for Operational Test and Evaluation (DOT&E) paints a gloomy picture of the F-35’s current state of readiness. A review from the Project on Government Oversight concluded that the report showed “the old problems are not going away, new issues are arising, and some problems may be getting worse.”

Recent test flights of the F-35 demonstrate the fighter is going to also have problems squaring off with other fighters in combat. In simulated dogfights the F-35 was continually bested by the older F-16 fighter and failed to maneuver effectively.

One thing the Pentagon did get right was political engineering. Parts for the F-35 are being manufactured in over 40 states with the US assembly area located in Fort Worth, Texas. If the F-35 program were to be killed, potential voters would lose jobs throughout the country — a clear incentive for Congress to keep the program going no matter the failures.