At the moment, no issue in American politics is more fraught than immigration. A surge in people hoping to enter the United States to seek political asylum in recent years has strained local, state and federal resources.

Beyond those strains, the increase also supercharged political commentary — particularly on the right, given that immigration is a federal issue and President Biden is a Democrat and up for reelection. At the extreme, the new arrivals (the numbers of whom are often exaggerated) have become fodder for anti-immigrant rhetoric that is at times explicitly racist or conspiratorial.

Texas Gov. Greg Abbott has, in practice and rhetoric, been at the forefront of combating the federal government’s handling of the surge. It’s not surprising that he should be, given how much of his state borders Mexico and, as a result, is tasked with accommodating the arrivals. In recent weeks, though, Abbott has taken steps that significantly increase his dispute with the federal government, both challenging federal authority and risking further escalation.

Below is a timeline of that tension.

Less than two months after Biden’s inauguration, Abbott announced that the Texas Department of Public Safety (DPS) would begin a crackdown on “the smuggling of people and drugs” into his state. He calls it “Operation Lone Star.”

“The crisis at our southern border continues to escalate because of Biden Administration policies that refuse to secure the border and invite illegal immigration,” Abbott wrote in a statement. From November 2020 to February 2021, the number of monthly encounters at the U.S.-Mexico border climbed from 72,000 to 101,000. (That latter number was lower than several months in 2019, when Donald Trump was president.)

An assessment of the operation published a year later by the Texas Tribune, ProPublica and the Marshall Project determined that many of the successes claimed by its proponents were inflated.

“In an internal email in May,” the Texas Tribune reported, “DPS officials said that the DOJ was seeking to review whether Operation Lone Star violated Title VI of the Civil Rights Act of 1964, which bars discrimination on the basis of race, color or national origin by institutions receiving federal funding.”

A news story from the El Paso Times noted that the deployment of razor wire along 60 miles of the border, meant to deter or block migrants from entering the state, had not been appropriately permitted by the federal government.

Abbott, who had declared a state of emergency in dozens of border counties because of the increase in migrants, responded on social media saying Texas “wasn’t asking for permission.”

The government of Mexico made a diplomatic outreach to the United States to object to Texas’s use of razor wire and Abbott’s announcement that he would float barriers in the Rio Grande.

“The Mexican Government requested the United States that the buoys mentioned, just like the razor wire fencing, should be removed from the channel of the Rio Grande due to obstruction and deviation of runoffs toward Mexican territory,” stated a news release from Mexico’s secretary of foreign affairs.

In a statement to the Dallas Morning News the following month, the U.S. government reiterated that it had not authorized Texas’s actions.

In a July 3 email to a supervisor, Trooper Nicholas Wingate described what he called “inhumane” orders he’d been given the previous month.

The Associated Press reported on Wingate’s allegations.

“[U]pon encountering a group of 120 migrants on June 25 — including young children and mothers nursing babies — in Maverick County, a rural Texas border county,” the AP wrote, “he and another trooper were ordered to ‘push the people back into the water to go to Mexico.’ ”

“In one instance, according to Wingate,” the report added, “a 4-year-old girl attempting to cross through razor wire was ‘pressed back’ by Texas National Guard soldiers in accordance with orders and that the child later fainted from the heat.”

The large orange buoys Abbott had announced the previous month begin to be deployed in the river.

Soon after the rollout, the federal government sued, citing, among other things, humanitarian concerns — and the fact that the state didn’t have permission to install the buoys. A few days before the suit was filed, USA Today documented migrant children who had been injured by the razor wire.

The location of the buoy installation is important: in the river near Eagle Pass, Tex. The border city is in the Border Patrol’s Del Rio sector, where encounters with migrants more than tripled between federal fiscal year 2021 and 2022. From 2022 to 2023, the increase was a more-modest 56 percent.

One body was found stuck on the buoys; Texas officials said the body had become lodged there after the victim had drowned further upstream.

A federal appeals court upheld a lower court’s September 2023 decision ordering Texas to remove the buoys from the water.

“For months,” the AP reported, “Texas has asserted that parts of the Rio Grande are not subject to federal laws protecting navigable waters. But the judges said the lower court correctly sided with the Biden administration.”

In a dissent, one judge argued that removing the buoys “won’t dissolve any tensions that the Biden administration said have been ramping up between the U.S. and Mexico governments,” the AP reported. That’s significant, too, as a reminder that border disputes have national ramifications, reinforcing why the federal government has primacy on border protection.

Abbott was undeterred, signing into law a bill that authorizes spending another $1 billion on border barriers and another that makes it a state crime to illegally cross into Texas from Mexico.

Democratic lawmakers demanded the Justice Department sue to stop the laws from being implemented.

The lawmakers’ letter argued that the state laws were “clearly preempted by federal law” and would likely result in racial profiling of Hispanics.

Tensions between Texas and the federal government now center on Texas’s seizure of a public park in Eagle Pass. The city’s mayor told the AP that he’d received a letter from DPS under the aegis of a state disaster declaration.

“This is not something that we wanted,” the mayor told the AP. “This is not something that we asked for as a city.”

Soon after, several migrants, including two children, were found to have drowned in the river near Shelby Park. The children were 8 and 10 years old.

Cuellar put the blame for the deaths on Texas, claiming that the Border Patrol had sought entry to the park to respond to claims of migrants in distress but were turned away.

This wasn’t accurate, as a later filing from the federal government made clear. The tragic drownings had occurred before the Border Patrol sought access to the area to respond to a different distress notification.

“It is impossible to say what might have happened,” the federal government’s top litigator, Solicitor General Elizabeth B. Prelogar, wrote in a court filing, “if Border Patrol had had its former access to the area — including through its surveillance trucks that assisted in monitoring the area.”

That filing was in support of the government’s appeal to the Supreme Court to allow it to remove Texas’s borders at the barrier. The government brought the case to the court in early January, arguing that Texas was preventing federal agents from doing their jobs.

That appeal was granted on a 5-4 vote in the Supreme Court. The dissenting justices were Samuel Alito, Neil M. Gorsuch, Brett M. Kavanaugh and Clarence Thomas.

Federal agents are now empowered to remove the razor wire placed by Texas.

Rep. Clay Higgins (R-La.), compared the situation to a “civil war” — one somehow fomented by the government itself. House Speaker Mike Johnson (R-La.) offered his support for Abbott on social media.

On Wednesday, Abbott released a statement challenging the authority of the federal government on the issue.

The response to Abbott’s argument from constitutional scholars has been broadly dismissive.

“This is nonsense,” one told Newsweek. ‘“Governors have no power to declare anything under the U.S. Constitution, nor does the Constitution give states any legal power to countermand the exercise of federal authority.”

Texas law enforcement officers continue to put up razor wire, despite the court’s decision.

Several Republican governors publicly sided with Abbott. The former president also weighed in on the matter. Trump, in a statement posted on social media, backed Abbott and “encourage[d] all willing States to deploy their guards to Texas to prevent the entry of Illegals, and to remove them back across the Border.”

In an appearance on Fox News Thursday morning, Abbott was asked if he would order DPS or other Texas agents to physically block federal officers trying to access the border near Eagle Pass.

“Texas has a right, as a state, to stop criminals from coming into our state,” he said. He added that Joe Biden “does have an option here” to enforce the law.

He did not respond to the actual question.