Trump is unpopular. That is no secret. In RealClearPolitics, his average is 39%.

A season of political rallies won’t improve that. Less campaigning might, advises Karl Rove in the WSJ.

It is senseless to help Democrats to easily tie a Republican candidate to voters’ low opinion of Mr. Trump. Karl Rove thinks that Trump should be raising money at fundraisers instead of inciting “an already excited Democratic electorate and make it more difficult for Republicans to contrast themselves with their opponents.”

Karl Rove knows of what he speaks. In 2006, an unpopular President George W. Bush’s Gallup approval rating in November was 38%.

Mr. Bush gave Republicans a better chance to keep their fire focused on their Democratic opponents.

The public had soured on the Iraq war. So while he raised oodles of campaign cash at private fundraisers, his campaigning was limited.

Still, as is customary in midterms, Republicans lost—30 House seats that year.

The Unpopular Iraq War

Lesson #1 learned: Fewer campaign rallies and more presidential actions that make a meaningful difference in people’s lives could produce a better outcome this time.

Next lesson learned: Although the Iraq War was unpopular, President Bush was seen as “a strong and decisive leader.”

He defended his actions, patiently explained the stakes in the war on terror, and was consistent and steady. Some people who didn’t like the war still trusted him because they felt, as president, he might know more than they did.

The Problem Is Messaging

Trump’s team should stop the bluster and wild promises on the Iranian conflict, forgo crude insults of allies and even foes, and return to the war’s original rationale.

From Trump: The “number one Goal is, and always will be, that Iran cannot have, in any way, shape, or form, a Nuclear Weapon.”

Trump needs to remind voters that the Iranian leadership has said for nearly a half-century “death to America,” and with a nuclear arsenal, they could act on that threat. And for God’s sake, writes Rove, “don’t TACO. That would only add to his image as weak, with consequences for domestic politics and the world.”

Karl Rove has offered versions of this case for presidential prudence and restraint more times, he says, than he can count.

That it’s ignored doesn’t make it any less right. Because there are good Republicans on the ballot who don’t deserve to be defeated but will be unless the president and his advisers forgo needless and unhelpful political spectacles this fall.