Columnist

The Trump administration, its foreign policy largely shaped by military men, urgently needs to tell Congress and the American people what we're doing in Niger — and where else we're doing it.

Like most Americans, I had no idea that roughly 800 U.S. troops were deployed in the arid, landlocked West African nation, where four soldiers were killed in an ambush on Oct. 4. Much more troubling is the fact that many key members of Congress — including Senate Minority Leader Charles E. Schumer (D-N.Y.) — were clueless as well.

"We don't know exactly where we're at in the world, militarily, and what we're doing," Sen. Lindsey O. Graham (R-S.C.), a champion of the war against terrorism, said Sunday.

President Trump, you will recall, promised during the campaign to scale back military deployments overseas. Of course, he promised a lot of things he cannot or will not deliver. But he has a duty to let Americans know to what ends U.S. military force is being used around the world — and where our troops are being sent into harm's way. The weeklong focus on Trump's phone call with the widow of one of the soldiers slain in Niger obscures the central question: Why were they there in the first place?

The Constitution gives Congress, and only Congress, the authority to declare war. U.S. troop deployments in Niger, Yemen, Somalia and many other countries — some we still may not know about — are being justified under umbrella laws, such as the 2001 authorization to use military force against al-Qaeda, or even the 1973 War Powers Resolution.

But the main target of anti- ­terrorism operations in Niger and elsewhere is the Islamic State, along with its affiliates. Congress needs to do more than investigate the deaths. It needs to authorize this conflict — or shut it down.

Trump is hardly the first president to ignore the Constitution in wielding military power. All recent presidents have done so. But the makeup of the Trump administration makes the need more pressing for Congress to reclaim its war-making powers.

Trump's chief of staff, John F. Kelly, was a four-star Marine Corps general. His defense secretary, Jim Mattis, was another four-star Marine Corps general. His national security adviser, H.R. McMaster, is a three-star Army general. All three men occupy positions usually filled by civilians.

Meanwhile, Trump's secretary of state, Rex Tillerson, is a businessman with no prior experience in government, politics or the military. As a practical matter, this means that the administration views the world's problems mostly through a military prism.

Generals whom I've met tend to be very smart — and tend not to be reckless with the lives of the young men and women in their charge. But Kelly, Mattis and McMaster have spent their careers wielding the mighty hammer that is the U.S. armed forces. And if what you know best is how to use a hammer, every problem tends to look like a nail.

Thus the generals convinced Trump to send more troops to Afghanistan rather than bring U.S. forces home. They persuaded him to increase our military involvement in Syria. They appear to have changed his whole worldview from "America first" neo-isolationism to conventional hawkishness.

I have mixed feelings about all of this. On most days, I feel that Kelly, Mattis and McMaster (along with Tillerson) are the last line of defense between our great nation and the abyss. Trump's impulsiveness, belligerence and insecurity would be a dangerous combination in any commander, let alone the commander in chief. But the president respects military men, meaning that the generals may be able to keep him from doing something rash and apocalyptic that could get us all killed.

On the other hand, Trump had a point when he pledged to reassess the role of the United States in world affairs. Insofar as he's doing anything, it's the wrong thing: He's giving us more military action and less diplomacy, when it ought to be the other way around. But Trump's generals are not likely to come up with any sort of new paradigm for U.S. foreign policy, and I worry that the default posture is waging endless war in more and more places — such as Niger.

Are U.S. troops necessary to contain the spread of Islamist militancy in the Sahel? Does the presence of U.S. forces win hearts and minds, or does it harden them against us? Are we prepared to stay for months? Years? Generations?

It's past time for the people's representatives in Congress to give Trump and the generals their marching orders.

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