REPUBLICAN PARTY officials in four states have decided not to hold presidential primaries or caucuses next year but instead simply to assign their delegates at the 2020 Republican National Convention directly to President Trump. Mr. Trump claimed the states made the decision themselves, but he explained how “having a primary election is very expensive” and they “don’t want to waste their money.”

No doubt democracy does require time, attention and some money. But unlike the president and the loyalists who do his bidding, we do not consider investments in democracy to be a “waste.”

Arizona, Kansas, Nevada and South Carolina decided in recent days to scrap their presidential nominating contests in favor of supporting the president. Other states, though not Iowa or New Hampshire, are said to be considering whether to follow suit. “As a general rule, when either party has an incumbent president in the White House, there’s no rationale to hold a primary,” said South Carolina GOP Chairman Drew McKissick.

Both parties have canceled primaries in some past years, but only when there were no declared primary challengers to the incumbent. That is not the case this year. Three candidates — former Massachusetts governor Bill Weld, former South Carolina governor and congressman Mark Sanford and former Illinois congressman Joe Walsh — are competing against Mr. Trump for the nomination. None of the three is seen at this moment as having much of a chance against Mr. Trump, who remains popular with the Republican base. But they have credible qualifications and alternative policies and worldviews. Why not let their voices be heard and give voters a chance to decide? Does Mr. Trump fear the challenge?

“Mr. Trump has not been bashful about his desire to avoid primaries or even elections,” said Mr. Weld. “He spoke admiringly of Xi Jinping getting rid of elections and talks about a third term for himself, which he has to know is not lawful. This is something that would be appropriate in a monarchy.”

Arizona, Kansas, Nevada and South Carolina should revisit their decisions. And if Mr. Trump is as confident as he professes about his ability to win it all, he should welcome the competition.

Read more:

Ed Rogers: Republicans are canceling primaries. Is Trump afraid of something?

Jennifer Rubin: Mark Sanford might be Republicans’ last chance

Henry Olsen: A Mark Sanford campaign will go nowhere fast

Jennifer Rubin: A guide for Trump’s GOP challengers

Jennifer Rubin: Why primary challenges to Trump are important