Eric Berger at Ars Technica notes that an amendment was attached to the National Defense Authorization Act that requires the government to consider the utility of reusable rockets for launching military payloads by House lawmakers. The amendment represents a win for companies such as SpaceX and Blue Origin which are developing reusable rockets and a challenge to United Launch Alliance to start doing the same. Congress was not always keen on reusability. What changed?

Elon Musk and Jeff Bezos have proven the reusability works

Reusability has been a theoretical concept for lowering the cost of space travel of decades.

For various reasons the space shuttle, though partly reusable, did not reduce the cost of space flight because of the substantial cost of turning around the orbiters between flights.

However, both SpaceX and Blue Origin have been proving in a visually stunning way that reusability can work. Blue Origin has flown its New Shepard suborbital rocket multiple times from its test range in Texas. The orbital New Glenn will have a similar capability. SpaceX has landed the first stage of the Falcon 9 multiple times on both land and sea and has recently reused one of these stages in a second flight.

Most analysts believe that both companies have solved the problem of turning around reusable rockets quickly and cheaply, with a resulting impact on the cost of space flight.

The capability is already having a salutary effect on commercial space flight with a race developing for who can provide the cheapest launches using reusable rockets.

The military is moving to reusability anyway

The Air Force has been operating a reusable space plane called the X-37B on classified missions in low Earth orbit for the past several years.

The X-37B has flown four long-term orbital missions, the most recent of which landed at the Kennedy Space Center just last May 2017. Speculation abounds about what the space plane is doing, ranging from testing space weapons to a prototype of the mysterious em drive that is alleged to provide thrust without propellant.

Meanwhile, DARPA is developing a reusable space plane that will be capable of conducting missions on demand with a turnaround time that can be measured in days or even a few hours, just like an aircraft.

The space plane would be a prototype of a spacecraft that can launch satellites on demand without a lot of preparation time on the launch pad. That capability will be critical in a future conflict in which Earth orbit becomes a battlefield, and the American military’s space assets are placed at risk.