The future of war is in outer space — and the U.S. is unprepared for the fallout.

Why it matters: An outbreak of space warfare would cripple the global economy by disrupting satellites used for everything from worldwide financial transactions to maritime navigation. It would also hinder the U.S. military's ability to conduct some of its key missions on Earth.

The dependence on satellites is precisely what makes them tempting targets for foes.

China has made major advancements, such as satellites with robotic arms that could disable U.S. equipment and lasers that can blind military space sensors.

Russia lags behind, but U.S. officials fear it may unleash an orbital nuclear weapon that "could pose a threat to all satellites and to the space-enabled services the world depends on."

What they're saying: Todd Harrison, the American Enterprise Institute's space expert, said "we've been under the illusion" that an adversary would target only military satellites and leave civil or commercial ones alone.…