CAPE CANAVERAL, Fla. — Vowing to reclaim U.S. leadership in space, President Donald Trump announced Monday he is directing the Pentagon to create a new “Space Force” as an independent service branch aimed at ensuring American supremacy in space. Trump envisioned a bright future for the U.S. space program, pledging to revive the country’s flagging efforts, return to the moon and eventually send a manned mission that would reach Mars.