Nations around the world are shoring up their defensive and offensive capabilities in space — for today's wars and tomorrow's.

Why it matters: Using space as a warfighting domain opens up new avenues for technologically advanced nations to dominate their enemies. But it can also make those countries more vulnerable to attack in novel ways.

• "Space has already been weaponized by just about any definition," Todd Harrison of the Center for Strategic & International Studies told me, citing work his organization has done to quantify the problem. "The question is, 'How are we going to respond?'"

Driving the news: From anti-satellite tests to establishing military branches dedicated to space, it is becoming an integral theater for militaries around the world.

• U.S. Space Command issued a rare statement in July calling out what it called an "anti-satellite weapons test" after a Russian satellite appeared to release a projectile near another Russian satellite.
• China reportedly has the technology to blind enemy satellites, according to a March 2020 report from CSIS.
• The U.S. and other nations rely on satellites to keep soldiers safe and get the lay of the land on the ground.

The state of play: More countries are relying on space in ways that benefit their societies, economies and militaries, so in some ways it's logical for them to create tools to help ensure access to orbit, Victoria Samson of the Secure World Foundation told me.

• The Space Force — which will have its one-year anniversary this month — was created in part to deter nations that threaten the U.S. in space.
• "While we will extend and defend America’s competitive advantage in peacetime, the ultimate measure of our readiness is the ability to prevail should war initiate in, or extend to space," Gen. John Raymond, the Space Force's chief of space operations, wrote in a planning document in November.
• France and Japan have also recently created their own military space divisions, showing how key space is becoming to military operations around the world today.

Yes, but: Some experts believe the U.S. is falling behind in efforts to secure its space infrastructure.

• While the U.S. is ahead of every other nation in its capabilities from orbit, the country's national security satellite infrastructure — which depends on a relatively small number of extremely expensive spy satellites — is vulnerable to attack.
• China, for example, sees its stance toward national security space in part as a way to counteract U.S. supremacy in orbit, according to a report from the Defense Intelligence Agency.

The catch: While wealthy nations can use space to their advantage in a variety of ways, doing so also creates new vulnerabilities. Establishing infrastructure in space is expensive, but destroying it is relatively easy.

• So far, countries have largely steered clear of destroying enemy satellites in part because of the far-reaching geopolitical implications of that kind of attack. And creating more space junk affects everyone in orbit, not just your enemies.
• But some experts are concerned that could change if new norms aren't established as nations work to build out military assets in orbit.

The bottom line: The future of warfighting will continue to rely on space as more nations recognize its importance as the highest ground.