To understand the American system, it is important to grasp how little power the American president has at his disposal.
Nevertheless, the American presidency was crafted for the unexpected moment, such as 9/11, where fundamental decisions need to be made within hours or days. When I vote for president, I ignore the policies and programs because they will rarely have the opportunity to pursue them. The American public is very clear in how it votes — it looks at the candidates, not the issues. This has been seen as a sign of shallowness. It is actually a sign of their deep understanding of the presidency.
The most important decisions presidents make are the ones they were never prepared for and have no policy for. Truman and Korea. Eisenhower and Suez. Kennedy and the Cuban Missile Crisis. Johnson and Vietnam. What their farm programs might have been is of monumental irrelevance. First, they can propose but Congress and the courts must enact. Second, it was the crises that defined their presidency. They had no policy for any of these, because they did not know what was coming.
When voters say they judge the person, what they are saying is that character is more important than the intentions. Intentions of presidents are crushed by history. Character, if you can glimpse it, tells you if the person is smart enough to understand the moment of history he is compelled to govern in, and the constraints it imposes on his choices. He needs to understand what is possible and impossible, in order that he have the ability to cause the least damage to the nation. Because in the end that’s what presidents must do. And the president must have the strange combination of hubris in imagining being president, and modesty, in understanding how little it means
https://geopoliticalfutures.com/thinking-about-the-american-presidency/