Houston

GARY Jacobs looks out over the Rio Grande from the deck of the clubhouse at a public golf course in Webb County, Texas.

It's a sunny morning, quiet except for the chirping birds and the thwack of clubs hitting balls.

"Where are you going to put the 30 feet?" he asks.

On this side of the river, a 270-acre plot of land Mr Jacobs and his wife donated to boost the profile of Laredo, a border town about 260km south of San Antonio.

On the other side, Mexico.

Mr Jacobs, like most of Laredo's 260,000 residents, is talking about US President Donald Trump's border wall, a project that's engulfing not just the border, but Washington and almost one million federal workers who went unpaid during the recent US government's partial shutdown.

Texas, a state where Mr Trump defeated Hillary Clinton by nine percentage points in the 2016 presidential election, illustrates the political complexity of his push.

After Mr Trump declared a national emergency last Friday to access billions of dollars in funding, some landowners along the US-Mexico line say they see a government land grab in their future.

The logistics of building a barrier are challenging enough. Thousands of creeks called "arroyos" carry rainwater from South Texas thunderstorms to the expansive river, which flows into the Gulf of Mexico.

A wall could act as a dam, trapping water on the US side and potentially complicating how Mexicans and Americans share the river for their water supply, says Mr Jacobs.

But his bigger problem with the wall is constitutional.

"The way the eminent domain laws are written, we have no rights," says Mr Jacobs, a former chief executive officer of Laredo National Bank before retiring. "That's the issue. It's not what they're going to build. It's how they're taking the land."

At least one lawsuit is challenging the Trump administration's emergency declaration, with others likely to follow.

The first, brought by the non-profit group Public Citizen on behalf of private landowners, argues that Mr Trump violated the US constitution's separation of powers when he invoked the National Emergencies Act.

About two-thirds of Americans oppose Mr Trump's expansive assertion of presidential authority, according to a CNN poll released last Friday.

Property seizure laws set up in the 1800s leave ranchers and landowners few options.

Often, work will already be underway or even finished before a judge rules on whether the money paid to property owners was fair restitution.

Apart from the US government claiming eminent domain to build roads, oil and gas companies will use it to lay pipelines through private property. Now, there's Mr Trump's wall.

"Philosophically, that's abhorrent to me," says Mr Jacobs, 77, who considers himself a Republican though he's voted for Democrats in the past.

Slap Texans with about 20 cases of eminent domain and Mr Trump's wall support among the state's Republicans will take a hit, Mark Jones, a political scientist at Rice University in Houston, said.

"Just as Texas Republicans are very supportive of having a strong level of border security, they also are very supportive of property rights," he added.

It's a particularly delicate issue in Laredo. At a Starbucks about two miles off the city's main highway, a father and son can be heard debating the merits of the wall and the threat illegal immigration poses to residents.

Business owners are reluctant to speak publicly about their opinion on Mr Trump's declaration out of fear of angering regular customers who hold opposing views.

While Mr Jacobs condemns the wall, he makes it clear that he advocates stricter enforcement of immigration laws and supports the local Border Patrol. BLOOMBERG