Howell and Moe reduce my book’s arguments to the title: “Trump’s behavior as president is best explained by seeing him as a toddler.” They describe such a thesis as radically incomplete: “we need to connect Trump to his political environment, to institutions, to the socioeconomic forces of our time—and, in particular, to populism.” It would be difficult to disagree with that assessment. Any political scientist ascribing an entire administration’s behavior solely to immature leadership is engaging in quite the audacious conceptual leap. Fortunately, I did not do that. Indeed, The Toddler in Chief’s first sentence reads, “In this book I make two arguments, one simple and one not so simple.” Howell and Moe focus only on the simple argument.

Perhaps they elided my other thesis because it contradicts their claim, elaborated over two books, that the US presidency is a weak institution. As I argued in my introduction, “formal and informal checks on the presidency have eroded badly in recent decades, and Trump assumed the office at the zenith of its power (p. 4).” The capacity of Congress, the judiciary, and the federal bureaucracy to constrain direct presidential action has been steadily ebbing since the post-Watergate reforms. Congress has voluntarily ceded several of its constitutional prerogatives to the president; political polarization has further hampered the legislature’s ability to engage in oversight. The courts have been reluctant to intercede in disputes between the branches of government. Presidents from both sides of the aisle have become more adept at bending autonomous bureaucracies to their will. Polarization has further hampered efforts to constrain Trump’s more egregious behavior, including his failure to concede the 2020 race. Little wonder that Polity recently lowered its scoring of US executive constraints.

These institutional shifts are the underlying antecedent conditions that explain why Trump’s individual psychology matters more than past presidents. Because recent presidents face fewer constraints on political behavior, variance in individual leader attributes explains more. This also explains why Trump’s presidential behavior seems increasingly erratic. As his initial senior staff—the so-called adults in the room—left the administration, their replacements were either unable or unwilling to constrain his myriad norm violations. Trump has shredded many of the “informal institutions” that were thought to bind the presidency.

Howell and Moe are correct to observe how Trump’s populist impulses explain some of his administration’s actions. But relying primarily on populism is an incomplete causal story as well: “as a populist, Trump is happy to exploit anger; as the Toddler in Chief, however, he is a slave to his own temper (p. 43).” Moe and Howell categorize Trump as a garden-variety populist and rely on societal causal mechanisms to tell their story, which can be a fruitful approach. What remains striking about the 45th president, however, was the persistent tendency of his own staffers, surrogates, and political allies to describe him in ways one would describe a small child. Sometimes analyzing the deviancy in the deviant case yields analytical leverage as well.