The Supreme Court rules 6-3 that federal officials may turn back asylum seekers at the US-Mexico border without processing their claims if migrants have not set foot on US soil.Justice Samuel Alito writes the majority opinion that someone stopped outside the line does not "arrive in" the US, and the Court overturns lower-court orders that had barred the practice.The decision supports the Donald Trump administration's metering policy, rescinds earlier protections and accompanies a separate ruling that allows ending temporary status for more than 356K Syrian and Haitian immigrants.Advocates warn thousands will wait in hazardous conditions in northern Mexico, Customs and Border Protection defends operational needs, and the ruling reshapes decades of asylum law.