As we noted in 2013, politicians seemed intent on buying 280 more M-1 Abrams tanks the U.S. military didn’t want or need. The M-1 Abrams is a formidable machine but not really suited for counterinsurgency operations, and the tanks run $8 million each. Last year we alerted taxpayers to the new fleet of presidential helicopters, each at $400 million, with the entire fleet coming in between $10 billion and $17 billion. That is hard to top, but the United States Air Force is making a gallant effort.

As Jonah Bennett explains in the Daily Caller, “Air Force leaders didn’t seem fazed recently when lawmakers pointed out that the service completely miscalculated the cost of its secretive Long-Range Strike Bomber program to the tune of $27 billion.” Last year Air Force leaders pegged the cost of the bomber at $33.1 billion from 2015 to 2014. This year it’s $58.2 billion for 2016 to 2015, an increase of 76 percent, which Rep. Jackie Speier, ranking member of the House Armed Services Committee’s Subcommittee on Oversight and Investigations, called “alarming.” In fact, according to the Air Force, the real cost for both fiscal periods is $41.7 billion. Air Force Chief of Staff Gen. Mark Welsh told reporters he was “surprised by the number” and that “it looked like the number had grown.” Air Force Secretary Deborah Lee James said someone in the process simply did the math wrong.

The Air Force may purchase between 80 and 100 bombers at a per-unit cost of $550 million. But that figure is a “wild fantasy,” according to T.X. Hammes, a U.S. National Defense University research fellow cited in Bennett’s piece, and the real per-unit cost of the bomber may rise to $3 billion. Bennett concludes that “cost-overruns are often a common feature of weapon acquisitions, mostly because providing low estimates and fast-paced schedule increase the likelihood of purchasing the weapon.” For taxpayers that’s only part of the story.

Whether tanks, ships, or planes, weapons systems always cost more than what their backers claim. Politicians may complain, but they usually go along if contractors for the projects are in their district. So military spending is a convenient conduit for pork. And the process continues whether or not the weapons system is suitable for the nation’s defense needs.