Surprise! The Supreme Court’s decision in Trump v. CASA, Inc. did not end birthright citizenship in the U.S. The decision merely trimmed the existing injunction in that lawsuit, so it now protects only the families, organizations, and the 22 states that filed or joined in that lawsuit. In response, just hours later, the ACLU quickly filed a new complaint challenging the Trump Administration’s executive order restricting birthright citizenship, this time as a nationwide class action. Not only did the filing confirm that the fight was far from over, it showed that litigators must always stand ready to pivot in the face of apparent adversity. In this way, the ACLU was sending a clear message: zealous advocacy remains a vital tool in the litigation toolbox.