Price tag for US 'war on terror' pegged at $5.9T

The U.S. will have spent nearly $6 trillion on various wars and military operations aimed at winning the war on international terrorist groups by October 2019, according to a study released Wednesday.

The $5.9 trillion assessment by Brown University's Watson Institute includes costs expected to be accumulated through the fiscal year that runs through September 2019, as well as past expenditures. It includes not just spending from the Defense Department, but all of government resulting as a consequence of the wars.

That includes related spending by the State Department and Department of Homeland Security, veterans care spending and interest paid on war debts.

As a result, the figure is significantly higher than the Pentagon's $1.5 trillion estimate.

"If the US continues on its current path, war spending will continue to grow," the report states, noting that even if the wars the U.S. embarked on following the Sept. 11, 2001, terrorist attacks are ended by 2023 the U.S. would be on track to spend an additional $808 billion.

"Moreover, the costs of war will likely be greater than this because, unless the US immediately ends its deployments, the number of veterans associated with the post-9/11 wars will also grow," it adds.

After Washington embarked on its military campaign against al-Qaeda, the group responsible for the 9/11 attacks, and the Taliban which offered it safe harbor, the U.S. invaded Iraq, and went on a global campaign of less expansive military efforts aimed at eliminating terrorist groups and their leaders.

That has included a robust targeted killings program, expanded special operations and a global intelligence collection program.

Spending in Afghanistan and Iraq has amounted to nearly $1.8 billion alone, despite a withdrawal of U.S. forces from Iraq that was completed in 2011.

But Washington re-entered the fray in Iraq and later Syria, deploying troops in support of partnered forces in the fight against Daesh, which overran large portions of the countries before being rolled back through an expansive American-led air campaign and train and advise mission for local forces.

Watson's study of the costs associated with the wars comes as a separate congressionally-mandated report warns the U.S. military "might struggle to win, or perhaps lose, a war against China or Russia."

Authored by the National Defense Strategy Commission, a bipartisan group of former security and military experts, the assessment warned Washington is not addressing the threats posed by Moscow and Beijing quickly enough.

"DOD and the White House have not yet articulated clear operational concepts for achieving U.S. security objectives in the face of ongoing competition and potential military confrontation with China and Russia," the report said, referring to the Department of Defense.

The commission called for a 3-5 percent increase in Defense spending above inflation in order to address the threats.

"Failing that, it may be necessary to alter the expectations of U.S. defense strategy and our global strategic objectives," it said.