On Thursday morning, President Trump tweeted, “As your President, one would think that I would be thrilled with our very strong dollar. I am not!” He went on to take the Federal Reserve to the woodshed, claiming that its refusal to reduce rates further is harming manufacturers like Caterpillar, Boeing, and John Deere: “They have called it wrong at every step of the way.”

This tweet barrage is the latest in a long line of presidential attacks on Fed Chairman Jerome Powell. So far, Powell has refused to take the bait. On July 31, when Powell announced a limited rate reduction and a reporter asked whether Trump’s criticism may have influenced his decision, Powell shrugged off the question, stating simply that the Fed is an independent agency that never takes political considerations into account.

Did Powell do the right thing? How should federal officials like Powell respond when the president attacks them? Before 2017, the question almost never came up. Regardless of their personal feelings, presidents did not publicly criticize current Fed chairmen or special prosecutors, let alone their own attorneys general.

Whether it was out of a patrician sense of decorum or a concern with the constitutional system of checks and balances, presidents held their views close to the chest. They expressed their displeasure by removing officials from office (when they could), not by attacking them while they remained.

President Trump has little respect for that tradition. In an interview with CNBC after a particularly harsh Twitter attack on the Fed, he stated, “I’m just saying the same thing that I would have said as a private citizen. So somebody would say, ‘Oh, maybe you shouldn’t say that as president.’ I couldn’t care less what they say, because my views haven’t changed.”

Powell is not the first of the president’s targets to adopt a policy of stoicism in the face of these assaults on agency independence. Special Counsel Robert Mueller remained silent while Trump repeatedly called his investigation into Russian meddling in the 2016 presidential campaign a “witch hunt” conducted by a band of “angry Democrats.”

In so doing, Mueller followed tradition. Prosecutors don’t normally address the public during the course of investigations, and when they do they give minimal information so as not to prejudice the defendant or poison the jury pool. Similarly, when he testified before Congress in July, Mueller refused to comment on political questions, sticking to the line that his report spoke for itself.

There are two strategies that federal officials could follow in the face of the president’s willingness to break with past norms. The first, embraced by Mueller and Powell, is to act as if it hasn’t happened, to continue as if we are living in the old world where politicians respected the need for independent agencies to pursue their work without the specter of political influence.

A second strategy is to engage the president in open debate, though perhaps with a more restrained tone. This strategy would be new but not wholly unprecedented. When Trump complained that “Obama judges” were biased against him, Chief Justice John Roberts issued a rare public statement designed both to counter the president and educate the public about the importance of an independent judiciary: “We do not have Obama judges or Trump judges, Bush judges or Clinton judges. What we have is an extraordinary group of dedicated judges doing their level best to do equal right to those appearing before them.” Whatever one may think on this score, Roberts opted not to remain silent and instead defended the institutional integrity of the courts.

Former Attorney General Jeff Sessions also eventually made a public statement after Trump consistently attacked him. For months Trump tweeted insults at Sessions for failing to investigate everything from Hillary Clinton’s email server to James Comey’s connections to Russia. He also criticized Sessions for failing to “protect” Trump by recusing himself from the Mueller probe. In a characteristic tweet, Trump called him “scared stiff and missing in action.”

“ Powell could have said that the American economy thrives because the Fed is insulated from politics. Mueller could have explained that political considerations play no role in prosecutorial decisions. ”

In an interview with Time magazine, Sessions explained that he thought he was right to recuse because “Congress passes a law. Judges follow the law, and nobody is above the law, including the judges and including the president.” He added that his loyalty is to that principle, to the rule of law, not to any one man.

Mueller and Powell could similarly have used the president’s attacks on them as an opportunity to explain to the American public why political influence on their work is dangerous. Powell could have said that the American economy thrives because the Fed is insulated from politics. Mueller could have explained that political considerations play no role in prosecutorial decisions. There is every reason to think that the quality of public debate, and the health of our public institutions, would have improved as a result.

An independent Fed, Justice Department, and judiciary all serve as checks on presidential power. When the President abides by the old rules, the officials who lead those institutions can as well.

But Trump isn’t playing that old game. If career civil servants don’t adapt to this new reality by answering his criticisms, professionally, as Roberts and Sessions did, they will leave the president unimpeded in a way that disserves our public institutions and has the potential to upset our republic’s delicate system of checks and balances.

Rebecca Roiphe, a former prosecutor in the Manhattan D.A.’s office, is a professor at New York Law School where she teaches legal ethics and criminal law. She also runs the Institute for Professional Ethics and co-directs the Criminal Justice Project at the school.