For more than a dozen years, the Pentagon has steadfastly stood behind the F-35 Joint Strike Fighter program as the next generation of jet fighters for the Air Force, Navy, and Marines, despite nightmarish development problems and daunting cost overruns.

The overall cost of developing and purchasing the jets currently is projected at $400 billion, while operating and maintenance costs could boost the overall price tag to nearly $1.5 trillion in the coming years. Lockheed Martin has weathered a vast array of design problems, most recently concerns over software and its computer system’s vulnerability.

Related: New Red Alert for Billions-Over-Budget F-35 Fighter

The latest indignity was reports that the F-35 lost to an F-16 during a mock aerial dogfight last January. The gold-plated new stealth jet couldn’t turn or climb fast enough to hit an enemy plane or to dodge the enemy's own gunfire, the pilot reported following a day of mock air battles back in January. "The F-35 was at a distinct energy disadvantage," the unnamed pilot wrote in a scathing five-page brief that War Is Boring obtained.

Throughout its controversial development, Department of Defense officials have asserted that they would need exactly 2,443 combat F-35s, plus 14 development aircraft, to deter and fight potential adversaries such as China. But with U.S. challenges abroad changing at a dizzying speed – including the rise of ISIS and other terrorists in the Middle East and Russia’s reemergence as a potentially dangerous foe, the Pentagon is rethinking its commitment to the F-35.

On Thursday, Gen. Joseph Dunford, the Marine Corps commandant who was nominated by President Obama to become the next chair of the Joint Chiefs of Staff, told the Senate Armed Services Committee that the F-35 development and purchasing plan is under review, as Defense One reported.

Related: How to Build a $400 Billion F-35 That Doesn’t Fly

“Given the evolving defense strategy and the latest Defense Planning Guidance, we are presently taking the newest strategic foundation and analyzing whether 2,443 aircraft is the correct number,” Dunford wrote in response to questions asked by the committee in advance of his hearing yesterday. “Until the analysis is complete, we need to pursue the current scheduled quantity buy to preclude creating an overall near-term tactical fighter shortfall.”

Here is a useful chart that shows the Pentagon’s current F-35 development plan:

Source: Defense One

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