Fourth, there is the intensity of his most devout supporters. While Trump has falsely boasted about many things, he was probably right when he said that he “could stand in the middle of Fifth Avenue and shoot somebody” and still maintain their support. Trump’s “tribal” supporters back him, not because of what Trump does or says, but because they want the affiliation they enjoy as Trump supporters. While these hard-core supporters were not sufficient to put Trump in office — experts believe this group is 25 percent to 40 percent of the electorate — even at the lower end of that range, they make up a majority of Republican primary voters in most Republican-held districts. That is a powerful check on Republican senators and representatives who might stand up to Trump — as House Speaker Paul D. Ryan (R-Wis.) learned when he was booed in his own district for distancing himself from Trump during the “Access Hollywood” conflagration.

And fifth, there is the frightening risk that Trump’s die-hard supporters are more devoted to Trump than they are to the rule of law. The United States prides itself on being “a government of laws, not of men,” but polls show that an increasing number of Americans generally, and Trump supporters specifically, have “lost faith in democracy.” Sinclair Lewis’s brilliant novel “It Can’t Happen Here” portrayed an alliance between populist rhetoric and corporatist policies that established an iron grip on government and trampled legal accountability. A Trump campaign email, sent the day the latest Comey allegations emerged, echoed Lewis’s depiction, labelling the growing scrutiny of Trump as “sabotage,” accusing government officials of being against an “America First agenda” and urging supporters to “be prepared to go into the trenches to FIGHT.”