WASHINGTON >> Aiming to succeed where his predecessors failed, Defense Secretary Jim Mattis called on Congress today to allow the military services to shutter excess bases — a move the Pentagon concludes will save billions of dollars but one that lawmakers have previously rejected.

Testifying before the House Armed Services Committee, Mattis sought congressional approval to start a new round of base closings in 2021. He said the department “currently has more infrastructure capacity than required for operations.” That outlook won’t change even if the service branches grow in size, he said.

The GOP-led Congress rebuffed the Obama administration’s requests to reduce the number of military bases. The Army and Air Force said they had vastly more space for training and basing troops than they need and trimming the surplus would generate savings that could be used to strengthen the military.

But lawmakers have refused to go along, questioning the data and the analysis the Pentagon used to make its argument for fewer facilities. Military installations are prized possessions in congressional districts.

Mattis appeared before the committee along with Marine Corps Gen. Joseph Dunford, the chairman of the Joint Chiefs of Staff, to field questions from lawmakers on President Donald Trump’s proposed military budget for the 2018 fiscal year, which begins Oct. 1.

Trump has proposed a defense budget for 2018 of $639 billion, which includes $65 billion for ongoing military operations. Yet Republican lawmakers are pressing for upward of $30 billion more to be added to the budget. They argue the extra money is needed to rebuild the military.

“We have spent six years just getting by, asking more and more of those who serve, and putting off the choices that have to be made,” said Rep. Mac Thornberry, R-Texas, the committee chairman.

The session Monday is likely to veer into questions about Russia, Qatar’s alleged support for terrorism, the Syrian civil war and other thorny subjects.

Mattis has been one of Russia’s most vocal critics. He’s called Russia the nation’s No. 1 security threat and accused its leader, President Vladimir Putin, of trying to “break” NATO.

Congress is considering slapping Russia with more sanctions in retaliation for Moscow’s meddling in the 2016 presidential election. Although the committee doesn’t have a direct role in the House and Senate intelligence committee probes into Russia’s election interference, Mattis may be asked about the Pentagon’s programs to help European allies counter Russia’s aggression.

Qatar has been engulfed in a political crisis that stems from accusations by its Arab neighbors that it supports terrorism. Qatar has denied the allegations, but its ties with Iran and embrace of various Islamist groups have brought intense scrutiny and made it a regional outlier. Last week, Saudi Arabia, Egypt, the United Arab Emirates and Bahrain severed ties with Qatar amid a slew of punitive measures.

Trump has sided with Qatar’s antagonists, calling on the Gulf state to stop “the funding of terrorism.” But Qatar has long been a U.S. ally. The country hosts roughly 10,000 American troops as well as the forward headquarters of U.S. Central Command.

A U.S.-backed Syrian opposition force has launched a wide offensive to seize control of the Islamic State group’s de facto capital of Raqqa in northern Syria. The U.S. has provided essential military and diplomatic support to the Kurdish-led Syrian Democratic Forces. Ahead of the battle for Raqqa, the Trump administration said it would begin supplying the Kurdish elements of the SDF with heavy weaponry.

The administration still is reviewing whether to send more American troops to Afghanistan after the top U.S. commander there told lawmakers he could use several thousand more to end the stalemate there.

The war in Afghanistan began in October 2001. The U.S. has about 9,800 troops in Afghanistan conducting counterterrorism operations against insurgents and training the Afghan army. Although they ended their combat mission against the Taliban in 2014, they are increasingly involved in backing up Afghan forces on the battlefield.

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