BROWNSVILLE, Texas (AP) — President Joe Biden and Donald Trump are in Texas for dueling visits to the U.S.-Mexico border. It’s a sign of how central immigration has become in the 2024 campaign. Biden wants to hammer Republicans for tanking a bipartisan border security deal on Trump’s orders. He landed in the Rio Grande Valley city of Brownsville, where border crossings are down lately. Trump journeyed 300 miles away at a state park that is at the epicenter of a standoff between Texas and the federal government over enforcement.