15 of the most expensive projects abandoned by the US military

The US military is unquestionably the world's strongest force with the world's largest defense budget.

But throughout the 2000s, the Pentagon spent $51.2 billion on 15 major programs "without any fielded systems to show for it," according to a new Center for Strategic and International Studies report.

The abandoned projects are largely due to a lack of funding attributed to the Budget Control Act and sequestration.

Sequestration, which is indiscriminate budget cuts across the board that affect every portion of the military equally, is the greatest threat to the US military currently, former Defense Secretary Robert Gates told Business Insider.

Below are a series of the military's modernization projects that were canceled partially due to a lack of funds.