US soldiers stand in formation during a military ceremony at the Storck barracks in Illesheim, Germany, Thursday, March 9, 2017. (Nicolas Armer/AP)

The Trump administration touts its new proposed budget for the Defense Department as one of the largest ­single-year increases in defense spending in U.S. history, fending off comparisons to earlier spending sprees by saying that they occurred during the country’s largest wars.

The administration argues in 2018 budget documents that spending $639 billion on defense, a $52 billion increase from the previous year, would lead to a stronger military and address concerns about how well-equipped and cared for the military is.

The budget request comes after Sen. John McCain (R.-Ariz.), chairman of the Armed Services Committee, criticized the president last month for not boosting defense spending enough. The Trump administration had said it was planning to boost defense spending to $603 billion, after McCain proposed spending about $640 billion in January.

The Trump administration said in new budget documents that its proposed increase “is exceeded only by the peak increases of the Reagan Administration and a few of the largest defense increases during the World Wars and the conflicts in Korea, Vietnam, Iraq, and Afghanistan.” Unlike past spending increases, the money proposed would “primarily invest in a stronger military,” rather than being consumed in combat operations, the administration said.

What's getting cut in Trump's budget

But the president must make that case while also expanding operations in several combat zones. Since Trump took over, the military has sent hundreds of troops to Syria in anticipation of an offensive on the city of Raqqa, launched dozens of airstrikes and a controversial ground raid in Yemen, and considered giving Special Operations units authority to launch missions in Somalia and Libya. Hundreds more U.S. troops may still be sent to Syria in coming weeks, and senior military officials are debating sending thousands more to Afghanistan.

The budget proposal documents include few specifics about how defense spending will be allocated but repeat administration promises to accelerate the military campaign against the Islamic State and boost cyberwarfare capabilities.

Trump's defense spending increase isn't extraordinary, but its impact could be

A senior military official, speaking on the condition of anonymity because he was not authorized to discuss the budget ahead of its rollout, said Pentagon officials also are anticipating the release Thursday of a budget amendment that will add $30 billion in defense spending in 2017.