"Now, we are into the detailed planning…because there are now a thousand decisions that have to be made…of how we move forward in establishing the service [Space Force] within the Department of the Air Force," Goldfein said during a discussion at the Brookings Institution in Washington, DC.
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US President Donald Trump will sign a directive later on Tuesday to establish the Space Force within the Department of the Air Force.
"We are the best in the world in space and our adversaries know it," Goldfein said. "They’ve been investing in ways to take away that capability in crisis or conflict … and we, as a nation, cannot let that happen."
His remarks come after on December 18, Trump issued a memorandum for then-Secretary of Defence James Mattis ordering the Pentagon to establish a US Space Command as a unified combatant command.
US Vice President Mike Pence said last year that the Space Command would integrate space capabilities across all branches of the military. He added that the administration was working with leaders of both parties in Congress to stand up the Space Force before the end of 2020.