President Trump’s plan to create a separate military service to defend America’s space assets hit a bipartisan wall of skepticism in the Senate Thursday, with leaders of the Armed Service Committee questioning the cost and structure of one of the president’s signature initiatives.

While senators generally agree that the United States needs to refocus efforts to protect American satellites and counter Chinese and Russian efforts to weaponize space, they question the need for a bureaucracy that includes two new four-star generals and a civilian undersecretary for a force of between 16,000 and 20,000 people, by far the smallest service.