In 2017, the chairman of the senate foreign relations committee, Bob Corker, called the White House an “adult daycare center” because of the immature behavior of President Donald Trump. With the risks of conflict around the world rising, it’s time for Congress to step up and provide adult supervision for the White House to keep the US safe.

It is an understatement to say that Trump’s foreign policy so far has been erratic and deeply dangerous. Trump appears intent on ripping up the diplomatic deal preventing Iran from getting a nuclear weapon. He has threatened war with nuclear North Korea. He has attempted to ban refugees and Muslims from coming to the US. He has embraced the authoritarian leaders of Russia and China as friends. The list goes on.

And yet, the US president has extensive power to craft and implement foreign policy. The constitution provides the president with tremendous authority, but the decades-long atrophy of Congress’s role as a coequal branch in executing US foreign policy has ceded even more power to the president. The president now has the ability to start wars anywhere in the world, and to use nuclear weapons on a moment’s notice.

As historian Arthur Schlesinger wrote in his classic, The Imperial Presidency: “What began as emergency powers temporarily confided to presidents soon hardened into authority claimed by presidents as constitutionally inherent in the presidential office: thus the imperial presidency.”

There is a robust, longstanding debate about the balance between legislative and executive branch powers on foreign policy. After Schlesinger first wrote about the imperial presidency, Congress attempted to re-establish its authority through the War Powers Act, imposing a number of requirements on the president’s ability to send troops into battle.

And while the extent of Congress’s role on foreign policy has ebbed and flowed ever since, especially since the terrorist attacks of 9/11 the power of the president to wage war and conduct foreign policy with few constraints has continued to grow.

Which brings us to today. Trump sitting in the Oval Office, sending out early morning tweets threatening war – without even the consultation of his cabinet and with no strategy in place – has raised the stakes on reining in the imperial presidency.

It would seem difficult to expect a Republican-controlled Congress to impose genuine constraints on a Republican president. And yet, on a few important occasions during Trump’s tenure, Congress has rejected actions by Trump that would have undermined national security: Congress forced Trump to approve new sanctions on Russia with veto-proof majorities; so far Congress has rejected Trump’s attempts to gut the budgets of the state department and USAid; and, to date, Congress has not taken Trump’s bait on the Iran deal by passing legislation that would sink it. But these are the exceptions to the norm of this Congress’ continued acquiescence to the executive branch on foreign policy – even bad foreign policy.

If there were ever a time for Congress to reassert itself on foreign policy, this is it.

First, Congress must use its legislative authority and power of the purse to force the administration to adopt reasonable policies. As the world faces the gravest crisis of forcibly displaced people since the second world war, Congress must provide funding and support for refugees and humanitarian assistance. Congress must pass legislation to protect special counsel Robert Mueller and the investigation into collusion between the Trump campaign and Russia. And Congress must continue to provide robust funding to the state department and USAid.

Second, Congress must hold regular, high-profile hearings that call senior administration officials to testify on the main threats confronting the US – and call them back regularly to provide updates on policy. From responding to Russian aggression to US policy on Syria to the status of North Korea policy, Congress must now play a leading role in keeping the administration honest.

And third – and most importantly – Congress must reassert its authority as a coequal branch of government in matters of war and peace. Today, the US is fighting conflicts in Afghanistan, Iraq, Syria, Somalia, Yemen, and beyond. The recent US military strikes on Syria – which could have resulted in escalation with Russia and Iran – did not have congressional approval. It is the responsibility of Congress to vote on any new US military intervention to ensure that it has the support of the people’s representatives.

Whether or not one believes Congress would realistically constrain a president of the same party, there is precedent. In 1966 Democratic Senator J William Fulbright held a series of public hearings on the conduct of the Vietnam war being waged by a president – Lyndon Johnson – of his own party, which helped spark a national debate.

From Vietnam to Iraq, the US has rushed into disastrous wars with limited congressional debate and quick acquiescence. Today, America faces the prospect of major conflict – with North Korea, Iran, Syria, Russia, China and more. With Donald Trump in the White House, there is no room for error. Congress must begin to act before it’s too late.