From [HERE] U.S. authorities detained more than 1.7 million migrants along the Mexico border during the 2021 fiscal year that ended in September, and arrests by the Border Patrol soared to the highest levels ever recorded, according to unpublished U.S. Customs and Border Protection data obtained by The Washington Post.

Illegal crossings began rising last year but skyrocketed in the months after President Biden took office. As CBP arrests increased this past spring, Biden described the rise as consistent with historical seasonal norms. But the busiest months came during the sweltering heat of July and August, when more than 200,000 migrants were taken into custody.

During a confirmation hearing Tuesday for Chris Magnus, the Tucson police chief Biden has nominated to lead CBP, Republican senators pressed him to characterize the surge as a “crisis.”

Magnus called it a “significant challenge,” echoing the Biden administration’s preferred term, adding that “the numbers are very high.” CBP is expected to release the 2021 fiscal year data later this week.

Border enforcement has become a major political liability for Biden, and the president’s handling of immigration remains his worst-polling issue. He promised on the campaign trail to make the United States more welcoming to immigrants, in contrast to former president Donald Trump, whose zero-tolerance family separations generated widespread outrage in 2018.

During the transition, Biden said he wanted to move cautiously on immigration policy and avoid ending up “with 2 million people on our border.”

Once in office, Biden quickly halted construction on the border wall, ended the “Remain in Mexico” policy, reversed key asylum restrictions and announced a 100-day pause on most deportations and enforcement by U.S. Immigration and Customs Enforcement.

Biden officials initially blamed the previous administration’s policies for the increase in border crossings and said migration pressures intensified as a result of the pandemic’s economic fallout. Many migrants have told reporters they opted to make the journey north, at great cost and considerable danger, with the belief that Biden would allow them to stay. A tight U.S. labor market became another pull.

Earlier this year, Biden directed Vice President Harris to address the “root causes” of migration from Central America’s Northern Triangle nations — Guatemala, Honduras and El Salvador. But the strategy has had little to no measurable effect, and Harris has distanced herself from the border and immigration issues generally.

The latest CBP data indicates that the administration’s challenges extend far beyond Central America. Mexico was the single largest source of illegal migration during the 2021 fiscal year, as the Border Patrol arrested more than 608,000 Mexican nationals. [MORE]