President Donald Trump announced Thursday the official establishment of the US military's Space Command. "Those who wish to harm the United States, to seek to challenge us on the ultimate high ground of space, it's going to be a whole different ballgame," Trump said at a White House ceremony marking the command's establishment. Space Command will become the 11th combatant command, joining the ranks of US Central Command, which oversees operations in the Middle East, and US Special Operations Command, which oversees Special Operations Forces.