Immigration was already bound to be a pivotal issue in this year’s elections. The standoff between Texas and the federal government, however, emphasizes just how egregious the problem has become—and highlights an especially glaring vulnerability for President Biden in November. Here’s a recap of the escalating standoff. Last week, Chief Justice John Roberts and Justice Amy Coney Barrett joined the Supreme Court’s liberal minority in a 5-4 ruling that allows U.S. Border Patrol agents to dismantle razor wire along the river in Eagle Pass, Texas, which the state had built to prevent illegal border crossings. The federal government claimed that...