Bernie Sanders and Mike Lee

Opinion contributors

Congress made history this week by passing a resolution that cuts off U.S. support for Saudi-led forces in the civil war in Yemen. This is the first time since Congress originally passed the War Powers Resolution in 1973 that we have used it to call on the president to withdraw from an undeclared war.

The passage of this resolution has implications far beyond Yemen and opens a much broader and extremely important debate about how and when the United States uses our military, and who must authorize that use.

Yemen is now experiencing the worst humanitarian disaster in the world because of the four-year-old Saudi-led intervention into Yemen's civil war. According to the United Nations, Yemen is at risk of the most severe famine in 100 years, with some 14 million people facing starvation. In one of the poorest countries on earth, because of this war, according to the Save the Children organization, an estimated 85,000 children have already starved to death over the last several years, and millions more face death if the war continues.

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Since the Saudi-led intervention began in 2015, the United States has been supporting it, refueling the Saudi coalition’s planes and assisting with intelligence. The bombs the Saudi-led coalition is using are American made. A CNN report found evidence that American weapons have been used in a string of deadly attacks on civilians since the war began.

As far as the people of Yemen are concerned, when they see “Made in USA” on the bombs that are destroying their country, it tells them that the U.S.A. is to blame.

This week Congress said clearly: No more.

Congress is taking back its war powers

Importantly, this resolution shows that Congress has begun to reassert its constitutional responsibility over war making. As we have both repeatedly stressed, Article I of the United States Constitution states that it is Congress which has the power to declare war, not the president. The Framers gave that enormously important responsibility to the branch of government that is closer and more accountable to the people.

Over many years, Congress has abdicated that responsibility to Democratic presidents and Republican presidents. This week, Congress reclaimed its constitutional authority by calling for the end of U.S. involvement in an unauthorized and unconstitutional war.

We must not stop with Yemen, however.

We believe that Congress has become far too comfortable with the United States engaging in military interventions all over the world. We have now been in Afghanistan for nearly 18 years, the longest war in American history. We have been in Iraq since 2003. Our troops are now in Syria under what we believe are questionable authorities, and President Trump has made clear he intends to keep them there despite earlier promises to withdraw.

On March 20, Amnesty International released a report alleging that U.S. drone attacks in Somalia had indiscriminately killed civilians, farmers, women, and an 8-year-old girl. These deaths, the report said, could amount to war crimes.

Draw the line and end decades of wars

According to the Trump administration, U.S. forces are currently fighting in seven different countries — Somalia, Afghanistan, Yemen, Iraq, Niger, and Libya — against militants linked to Al Qaeda, the terrorist group that attacked the United States on September 11, 2001. The administration justifies these interventions under the Authorizations for the Use of Military Force passed by Congress in in 2001 and 2002.

It is time for Congress to ask whether, nearly 18 years after 9/11, we really want to continue to be involved in these wars for another 18 or more. According to a recent study by the Costs of War Project at Brown University, the War on Terror will have cost American taxpayers almost $5 trillion through Fiscal Year 2019. When taking in to account future health care obligations for veterans injured in post-9/11 wars, the bill comes closer to $6 trillion.

Even after this enormous expense, the world has more militants, not fewer. A November 2018 report from the Center for Strategic and International Studies found that the number of militants has continued to grow. “Despite nearly two decades of U.S.-led counterterrorism operations,” the report said, “there are nearly four times as many Sunni Islamic militants today as there were on September 11, 2001.”

The time is long overdue for Congress to reassert its constitutional responsibility over war making. We need a serious national debate over when and where we put our military in harm’s way, and about how much we are prepared to spend on those interventions. Congress’s historic vote on Yemen this week is an important beginning in that process, now we must continue forward.

Bernie Sanders is an independent senator from Vermont. Mike Lee is a Republican senator from Utah. Follow them on Twitter: @SenSanders and @SenMikeLee