Vice-presidential nominees are supposed to be attack dogs, sparing the person at the top of the ticket from being accused of excessive partisanship. Richard Nixon ably performed this service for Dwight Eisenhower in 1952 and his own vice-presidential nominee, Spiro Agnew, returned the favor in 1968. It is not usually a graceful job, particularly for Republicans.

But J.D. Vance is not very good at covering for Donald Trump. He is staid, pompous, nasty and, most importantly for the GOP, ineffective. He gets into difficult situations, such as when he was roundly booed at the Fire Fighters Union meeting. Vance clearly did not know his audience and managed to illicit the worst possible response. His only service for Trump is that he gets more unfavorable publicity than his boss.

On top of this he goes down rabbit holes, denouncing childless women in particular and childless couples in general. These are important but not pressing issues for a Republican candidate to emphasize. Every time he speaks on such topics, Trump is forced to state that he is not as anti-abortion, or opposed to IVF, as his right-wing partner. In turn, his credibility, never that strong, is further questioned.

Perhaps Trump’s campaign team assumes that Vance will protect his flank, allowing the Presidential nominee to muddy the waters on reproductive freedom. But Vance is so poor at protecting his partner, that Trump accused the GOP in Florida of being unreasonable in pushing a “six-week” abortion ban.

All of this takes away from Trump attacking the Democratic ticket, and perhaps that is central to his problem. Trump prefers to take the lead role in the attack. He’s skilled at invective and is relentless in the pursuit of his opponents. Instead, he has been stale in his speeches, repeating weeks-old lines. Mike Pence was better at being a sidekick for Trump; Vance’s insistence on taking the lead manages to interfere with the top of the ticket.

It is much like Thomas E. Dewey’s 1948 attempt to defeat Harry Tuman. In 1944 Dewey was brash and aggressive; in 1948 he became predictable and dry. Since Milwaukee Trump has repeated old fashioned attacks in uninteresting venues. For the first time in his long association with the Republican party, Trump is behaving relatively normal. He has become a Mitt Romney who has a fondness for insult comedians. And Vance has played a role in this metamorphosis in that he cannot duplicate Trump.

Perhaps Vance can take the lead on the issue that helped him get on the ticket, which was foreign policy. He was most effective on criticizing Joe Biden’s policy concerning Ukraine. But you hear very little about the subject from the GOP’s Vice-Presidential nominee. No comment about forever wars, just cracks about “childless cat ladies.” In Vance’s defense, he has been given a bad role, dwelling in issues that anyone would be hard-pressed to advance.

It is ironic that Tulsi Gabbard has taken the lead in helping Trump to prepare for the debate. Gabbard, who is very clear on foreign policy, may have been a better choice than Vance. But she was probably out of the discussion because she could not conform to a role more appropriate for Nikki Haley. Vance is not good at playing it either, which might explain Republican problems.