Just as physicists spend decades seeking to resolve the seeming paradox that a photon is both a wave and a particle, observers of U.S. politics continue to struggle with the reality that Donald Trump is both an exceptionally weak president and an authoritarian threat. Since 2017, many commentators have treated this question as binary, suggesting that Trump’s failures as a president should invalidate any concerns over what his White House tenure might mean for the future of our democracy. But that’s an incorrect — and dangerous — assumption.

The latest example of this line of thinking comes in New York magazine from political theorist Corey Robin, who denounces “pundits and scholars [who] have been sounding the alarm over the authoritarian or fascist turn of American politics.” To the contrary, he says, Trump’s “weakness has been evident from the beginning.” Robin means to criticize those journalists whose emphasis has swung between the weakness and authoritarian hypotheses, but in the process, he collapses these ideas back into the same false dichotomy. “Where did all the tyranny go?” Robin asks, citing numerous examples of Trump’s defeats that he suggests means the president is a “flailing conservative” rather than “an ascendant authoritarian.”

Robin directs particular fire at advocates of the so-called Green Lantern Theory of the Presidency, a term I coined to describe the idea that a president’s failure to achieve his policy goals is simply due to a lack of will to pursue their goals forcefully enough. Barack Obama’s critics often leveled these types of charges against him, saying he should have taken some unspecified action to enact liberal policies like gun control that could not overcome Republican opposition in Congress. During his run for the White House, Trump played on these notions, claiming that previous presidents lacked the will to make trade deals that would benefit U.S. workers. If he were president, Trump implausibly claimed, he could negotiate deals that would reverse structural changes in the economy.

Trump has revealed a weakness that is unprecedented in recent history.

But, contrary to Robin’s analysis, Trump’s failures do not invalidate the Green Lantern Theory; they support it. The theory is based on the simple premise that presidential compromise and policy failures are not the result of a lack of will but of the limitations of an office that is constitutionally weak, especially in domestic policy. Despite plenty of willpower, for instance, most chief executives struggle to change public opinion and attract support for their initiatives in Congress. Trump has experienced these realities firsthand. He has failed to achieve the easy wins he hoped in negotiating trade deals — the changes he made to the NAFTA were largely minor, and he has escalated a trade war with China with little to show for it to date. In domestic policy, Trump has faced similar obstacles — his hardline approach to immigration policy actually increased public support for immigration, and he could not induce Congress to fund his border wall even after a government shutdown.

But Trump’s failures go beyond what the Green Lantern Theory predicts; he has revealed a weakness that is unprecedented in recent history. The president of the United States is now repeatedly ignored and rebuffed by his own staff, party, and the rest of the federal government. Trump declared the U.S. was leaving Syria, and now hundreds of troops are staying. When he demanded his fellow Republicans prioritize the border wall, they instead pursued tax cuts and health care repeal. Trump can’t even get the military to hold the authoritarian-style parade he’s long demanded.

However, none of these facts invalidate the threat that Trump poses. As he has shown, weak presidents can still inflict damage on democracy while in office. In fact, the slow erosion of democratic norms and institutions — not coups or revolutions — is the most common threat to democratic stability in recent decades. (Think of the recent slide toward authoritarianism in Russia, Turkey, or Hungary, not the fascism of mid-20th century Europe.) While our institutions have limited the damage Trump has been able to inflict so far, there is strong expert consensus that U.S. democracy has degraded since he took office.

For instance, Trump’s weakness may frustrate his ambitions in the legislative sphere, but he can still erode protections against executive overreach in his use of national emergency powers to try to fund a border wall or undermine government efforts to punish and prevent foreign influence in elections. The powers of the presidency are potentially expansive even in the hands of a weak president, as Daniel Drezner emphasized in the Washington Post.

Similarly, Trump’s rhetoric can still be dangerous even if his worst impulses are checked on policy. Trump has endorsed a long list of authoritarian actions ranging from law enforcement investigations of his political opponents to criminal assault against a journalist. He echoes Stalinist rhetoric in calling the media the “enemy of the people” and spoke favorably of white nationalist protesters. These statements risk normalizing hatred and violence and undermining democratic norms, particularly within Trump’s party, where his influence is greatest. Robin suggests that critics of the authoritarian threat have reversed themselves on the power of presidential words, but as political scientist Emily Thorson points out, the articles he cites actually focus on how Trump could change Republican politics — a threat even if his words fail to produce immediate anti-democratic actions.

Finally, past presidential weakness does not guarantee future democratic stability. A weak president can actually be more dangerous, as observers have emphasized. Tom Pepinsky, an expert on authoritarianism at Cornell University, notes that “weak leaders have every incentive to portray themselves as stronger than they are in order to get their way. They gamble on splashy policies. They escalate crises.” Similarly, Bloomberg columnist Jonathan Bernstein predicted back in November 2017 that “weak presidents tend to lash out, using the powers of their office to attempt to get what they can’t by normal bargaining” — exactly what Trump did in declaring an emergency when the government shutdown failed to get wall funding enacted. What will he do the next time he is defeated?

Trump’s failings in office should not blind us to the threat of democratic erosion in the United States. History is full of authoritarians who overcame initial political defeats and later acted on their prior rhetoric. We should heed the lesson they offer.