"A single digit, not a double digit… Might be lower than five, it could be lower," Shanahan told reporters when asked about the possible cost of the Space Force in billions of dollars, as quoted by The Hill outlet on Thursday.
The statement comes as US President Donald Trump said last month that the United States was creating a space force to catch up with China and Russia.
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The US defence budget for the fiscal year 2019, which began on October 1, includes the re-establishment of the US Space Command. It also prescribes the US Missile Defense Agency to begin work on deploying systems to track and intercept ballistic missiles in space. According to the document, the development and deployment of a Sustainable Space Sensor Architecture should be completed before 2023, while the missile interceptor system may be deployed later.
According to a memo by US Air Force Secretary Heather Wilson that was leaked in September, the United States may need nearly $13 billion to create this new branch of the military within the project's first five years.