A single-day national primary would be a good thing for a number of reasons. The first is simply that it would allow more Americans to have a say in what candidates our major parties nominate. I have a great deal of affection for residents of both Iowa and New Hampshire, but I would be hard pressed to say that either is representative of the United States as a whole or especially deserving of the attention that is lavished upon them every four years. Making presidential nominations more democratic is, after all, the reason primary contests exist in the first place. Before 1972, primaries, if they were held at all, were essentially straw polls; nominees would be chosen by party insiders without regard for the outcome. It was only the outrage generated by Hubert Humphrey’s nomination in 1968 that gave rise to the idea that actual voters should get to choose for whom they would be voting.
Second, and even more important, having a national primary would reduce the length of the campaign season. It would be a good thing for all of us if, instead of months and even years of speculation about how many bacon-wrapped blueberry pieces on a stick Joe Biden was going to eat, we could all vote in the primary of our choice on the same day, telescoping millions of words of pointless speculation into a single day.