The United States faced a heavy burden in establishing its entitlement to a preliminary injunction enjoining Arizona from enforcing S.B. 1070. The United States fell far short of meeting that burden. The district court’s finding that the United States is likely to prevail on its claims that sections 2(B), 3, 5(C), and 6 of S.B. 1070 are preempted failed to apply the correct standard for the United States’ facial challenge to these provisions, failed in its analysis of Congress’ intent, and erroneously accepted at face value all of the United States’ factual assertions. The serious errors in the district court’s preliminary injunction order require that the order be vacated.