But since we have the dissent opinions, it's not tricky at all to see why they are dissenting.

Alito and Thomas straight up believe that the constitution does not provide birthright citizenship and the executive order is valid. Gorsuch mostly agrees but makes an exception if the parents plan to stay in the US. Kavanaugh agrees that birthright citizenship is not provided by the constitution, instead he argues its a federal statute that congress can overturn (but the president cannot)

https://www.scotusblog.com/2026/06/supreme-court-strikes-dow...