John J. Pitney Jr.

Donald Trump’s small band of intellectual defenders can no longer claim that he is good man. Instead, they say that his dishonesty and cruelty are acceptable because Congress could check him if he really got out of hand. Like so much else about the Trump campaign, this assertion rests on fantasy.

Although an unusual number of Republican lawmakers have come out against him, most have not. Several who called on him to drop out of the race have since said that they will vote for him anyway. Why are so many siding with a candidate who is so unfit? High on the list of probable motives is fear of a challenge in a future GOP primary. In recent years, some high-profile Republicans have either lost to a hard-line conservative (for instance, former House majority leader Eric Cantor of Virginia) or endured an unexpectedly tough battle (Sen. Thad Cochran of Mississippi). Trump supporters are vocal and zealous, so it is not hard to picture them working to oust Republicans disloyal to their man.

If GOP lawmakers are cowering before candidate Trump, how could they stand up to President Trump? In addition to his wealth and political base, he would wield the vast power of the executive branch. There is little doubt that he'd use it to punish those who displease him. After House Speaker Paul Ryan said he'd no longer defend his bad behavior, Trump hinted at a leadership purge, saying, “I would think that Ryan wouldn't be there.”

In light of such threats, Republicans would hesitate to oppose Trump’s choices for federal office or hold tough investigations into his management of the government. And it is hard to imagine that they'd reach for the ultimate weapon of impeachment. "I could stand in the middle of 5th Avenue and shoot somebody and I wouldn't lose voters," Trump said back in January. That is only a slight exaggeration, at least as far as it applies to his core supporters.

Maybe congressional Republicans would suddenly get a miraculous infusion of courage and institutional fidelity. And maybe rainwater would turn into beer. But I would not count on it. As Ryan acknowledges: “Under both parties, the presidency keeps breaking the rules, and Congress keeps allowing it to happen.”

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Even if lawmakers wanted to put some kind of restraint on a Trump administration, they'd have only limited ability to do so. True, they could turn down some of his legislative requests, but they'd have a hard time tracking what his administration was doing. In “The Big Lobotomy,” journalists Paul Glastris and Haley Edwards write, Congress has cut way back on its capacity to oversee the executive branch. They note that the Congressional Research Service and the Government Accountability Office (Congress’ official “watchdog”) both operate at about 80% of their 1979 capacity.

The feebleness of congressional oversight has been problem even under a more-or-less normal person such as Barack Obama. It would be a disaster under a fanatically secretive person such as Trump. He won’t release his tax returns, and he makes his campaign aides sign non-disclosure agreements. The mind boggles at the information that his administration would withhold from Congress and the American people.

Congress has always been at a disadvantage in checking the president’s power over foreign policy and national security. On hundreds of occasions, presidents have used military force overseas without congressional approval. In 1973, Congress tried to curb such activities by passing the War Powers Act. Numerous military actions over the past 43 years suggest that this measure is not effective.

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The law requires the president to seek congressional authorization within 60 days of starting military action. This requirement does not limit the president’s power to launch a nuclear attack — a process that would take less than an hour. Since the bombing of Hiroshima, a dozen chief executives have held this power, with no real external check at all. Each of these 12 presidents made mistakes, and some of them did very bad things, but none was reckless enough to start a nuclear war. That is why we are alive today.

Trump probably does not hope for Armageddon, and it seems unlikely that he would strike at a friendly nation. But it is all too plausible that his ignorance and rashness could start a crisis that escalates into a nuclear exchange. No one should vote for him in the hope that Congress could stay his hand — because it can’t.

John J. Pitney Jr., a former policy aide to Republicans in Congress, is the Roy P. Crocker Professor of Politics at Claremont McKenna College. Follow him on Twitter @jpitney.

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