President Trump attended Supreme Court oral arguments on birthright citizenship, marking the first time a sitting president witnessed oral arguments on a case directly affecting his executive order. The justices showed skepticism toward the administration's argument that the 14th Amendment doesn't guarantee citizenship to children of undocumented immigrants, with even conservative justices questioning the government's legal theory as "quirky" and historically weak. Chief Justice Roberts and Justices Barrett and Gorsuch—all conservatives—expressed serious doubts about the administration's argument that children of illegal immigrants lack birthright citizenship, suggesting the executive order faces an uphill battle at the Supreme Court. The Trump administration's case relies heavily on reinterpreting the 1898 Wong Kim Ark decision to emphasize the word "domicile," but justices noted domicile appears 20 times in that opinion and questioned why it wasn't mentioned in 14th Amendment debates if it were truly central.