At two Texas border towns both President Biden and former President Trump made duelling visits.
They were 300 miles apart but with an identical aim, to eke out political advantage from the immigration crisis which will be one of the defining issues of the 2024 election.
The Biden administration has presided over a record number of border crossings, a surge which Republicans have used to characterise the president as being weak on the issue.
In Brownsville, Texas, a town which historically has large influxes of migrants, Mr Biden made only his second visit to the border, but this time promised change.
“It’s real simple. It’s time to act, it’s long past time to act,” he said.
He also accused Mr Trump of political point-scoring after a bipartisan bill, which would have resulted in a crackdown on the border, was thwarted by Republicans who were being egged on by the former president.
“You know and I know it’s the toughest, most efficient, most effective border security bill this country’s ever seen,” he said.
“So instead of playing politics with the issue, why don’t we just get together and get it done?”
Immigration is a happier hunting ground for Mr Trump. His rhetoric on the issue has become more extreme in recent months, notably when he said immigrants were “poisoning the blood” of America.
But it only seems to have enlivened his base, with the polls suggesting his advantage over President Biden on immigration is growing.
Speaking from Eagle Pass, Texas, with the backdrop of a razor wire fence, Mr Trump seized on the flashpoint of the murder of Laken Riley, a 22-year-old nursing student killed in Georgia.
The man charged with her murder is a Venezuelan migrant, previously arrested for crossing the border illegally in 2022 and then released, before being arrested in New York and released again.
“The United States is being overrun by the Biden migrant crime,” he said. “Migrant crime is a new form of vicious violation to our country.”
Mr Trump’s words are reverberating in other border cities, too.
In the remote town of Jacumba Hot Springs, California, where migrants often cross the border, I meet a group of a dozen veterans outside a casino.
They are part of an organised convoy heading to the border to, they say, shore up defences.
I ride along with Derrek Cardinale, a former marine and estate agent, in his white pickup truck. The conversation quickly turns to immigration and the terror threat.
“It only takes one to cause another 9/11 or another October 7th in Israel,” he says.
“I have four kids, and seeing this young girl Laken Riley recently being murdered by a Venezuelan who is here illegally. My wife travels with my four kids and she doesn’t have the training that I do to be aware all the time, so it definitely worries me.”
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When we get to the border wall separating Mexico and the United States, where the 30ft-tall fence ends, the group have bundled out razor wire on top of boulders where migrants might scramble.
“What happens if a person gets caught on it?” I ask.
“Well it definitely hurts,” one woman replies. “It’s about making sure it’s painful enough that they at least can’t come in this way.”
‘It’s ugly, it’s dangerous’
For the migrants who do make it through, their first few hours in the United States often involves sitting on pavements in downtown areas outside detention centres, waiting for buses, first to transport hubs and then to the airport.
Waiting on a pavement in central San Diego I find Maria, a 21-year-old from Ecuador.
She says it has taken her a month and 12 days to get to the US after fleeing gang violence in her home country.
“The situation in Ecuador, it’s ugly, it’s dangerous,” she says. “We came over here for a better future, to support our family and to stay for a while.”
Many of the migrants wear tracking devices placed on them by border control services, to monitor them while their asylum claims are processed.
Immigration is not just a potent political issue in border cities, many of the migrants are heading to destinations across the US, including Miami, Chicago and New York.
At San Diego’s marina, locals and tourists watch the sunset. Laurie and Tom, from Denver, Colorado, say the immigration system in their city can’t cope.
“We can only handle so many people,” says Laurie.
“We only have the resources for so many and allow people just to keep coming in and coming, and something’s going to break.”
Robin and Greg from Wisconsin, say they will vote for Donald Trump if he is an option in November because they believe he will protect America’s borders.
“I think anybody would protect the border better than the Biden administration,” says Greg. “Regardless of who that is.”