WASHINGTON — A surge in migrant traffic across the Southwest border into Texas has resulted in a milestone: the front line of the battle against illegal crossings from Mexico has shifted for the first time in over a decade away from Arizona to the Rio Grande Valley of South Texas.
This shift has intensified a bitter debate under way in the Senate over whether the border is secure enough now, or ever will be, to move ahead with legislation that could give legal status to millions of illegal immigrants already here.
On Monday, the Senate was scheduled to resume a long series of votes on an immigration bill that is promising to end a cycle — playing out since the early 1990s — in which each time the Border Patrol cracks down in one enforcement zone along the border, migrants move to another.
Now the Rio Grande Valley has displaced the Tucson enforcement zone as the hot spot, with makeshift rafts crossing the river in increasing numbers, high-speed car chases occurring along rural roads and a growing number of dead bodies turning up on ranchers’ land, according to local officials.
“There is just so much happening at the same time — it is overwhelming,” said Benny Martinez, the chief deputy in the Sheriff’s Department of Brooks County, Tex., 70 miles north of the border, where smugglers have been dropping off carloads of immigrants who have made it past Border Patrol checkpoints.
The increase in Texas is taking place even as the Obama administration says it has achieved unprecedented control over the border with Mexico. The administration, President Obama said last week, has “put border security in place,” with illegal crossings “near their lowest level in decades.”
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