When all right-thinking people in the nation’s capital seem to agree on something — as has been the case recently with legislation imposing new sanctions on Russia — that may be a warning that the debate has veered into an unthinking herd mentality.

Sanctions were already an overused tool of foreign policy before President Trump this week peevishly signed into law a measure imposing new penalties on Russia, Iran and North Korea. The House had passed the legislation last week 419 to 3; the Senate voted 98 to 2. That’s the congressional version of a stampede. Congress also gave itself the power to review any presidential attempt to undo the Russia sanctions specifically.

Trump appended a signing statement arguing that the legislation was “seriously flawed” because it “improperly encroaches on executive power.” It’s heretical to say so, but he may be right. This legislation limits presidential flexibility at the very time it may be most needed to conduct delicate negotiations with these adversaries.

If this were any other president than Trump, and any other antagonist but Russia, I suspect Trump’s arguments would have gotten more support. When he wrote in the signing statement that “the Framers of our Constitution put foreign affairs in the hands of the President,” he was hardly an outlier. That has been the traditional consensus view.

President George W. Bush regularly issued signing statements when he thought Congress was encroaching on executive power. So did President Barack Obama, as in a July 2009 statement protesting congressional dictation of policies toward the World Bank and the International Monetary Fund.

This time, House Minority Leader Nancy Pelosi (D-Calif.) simply tossed the signing statement into the basket of collusive Trump behavior. “The Republican Congress must not permit the Trump White House to wriggle out of its duty to impose these sanctions for Russia’s brazen assault on our democracy,” she said. Trump has earned this mistrust, but Pelosi’s red-hot rhetoric probably backfires by turning off people who aren’t already convinced.

Trump is as sanctions-obsessed as Congress, it should be noted. Last week, his administration imposed its own new sanctions on current and former Venezuelan officials and, this week, against Venezuelan President Nicolás Maduro . Meanwhile, Trump is threatening to decertify the Iran nuclear deal and levy additional sanctions, even though his CIA director says Tehran is technically in compliance. This, truly, is a season for hypocrisy.

The best argument that sanctions are overused was made in March 2016 by Jacob Lew, then treasury secretary, in an interview with me and in a subsequent speech at the Carnegie Endowment for International Peace. His focus at the time was on congressional efforts to prevent Obama from easing sanctions on Iran as it complied with the nuclear deal.

Lew explained back then: “Since the goal of sanctions is to pressure bad actors to change their policy, we must be prepared to provide relief from sanctions when we succeed. If we fail to follow through, we undermine our own credibility and damage our ability to use sanctions to drive policy change.”

Lew noted another problem with the United States’ growing tendency to use sanctions as a cure-all in foreign policy. By limiting access to U.S. financial markets to punish countries whose behavior we don’t like, the sanctions tool ultimately risks undermining the primacy of the dollar and U.S. financial institutions.

I asked Lew on Thursday whether he’d still make the same argument. “My views haven’t changed,” he said. “I continue to think that the executive branch needs to have the tools to increase pressure and release it at the appropriate time. That’s very complicated if you have to go back through Congress.”

Don’t misunderstand me. In questioning congressional review of sanctions, I’m not excusing Trump’s behavior. His non-response to Russia’s well-documented meddling in the 2016 presidential election has been outrageous. Sacking special counsel Robert S. Mueller III would be even worse — an assault on our constitutional rule of law.

(Gillian Brockell,Kate Woodsome,Karen Attiah,Daniel Mich/The Washington Post)

But even if you think this story is headed toward impeachment, the United States still has to conduct foreign policy in a dangerous world for many months, if not years. We hear many Watergate analogies these days, but let’s not forget the foreign policy version — of a weakened, erratic president facing regional wars and global crises, as in 1973 and ’74. Like President Richard Nixon, Trump needs good foreign policy advisers (he seems to have them) and some maneuvering room.

The Trump-Russia file stinks. But this doesn’t mean that every congressional zinger fired at Russia is sensible, or that every Trump attempt to preserve executive authority is a potential conspiracy count. When Washington legislators start making arguments that, in other circumstances, they would reject, you know something is wrong.

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