In the face of Russian missile and drone attacks, Ukraine needs more than weapons to protect itself. Satellites provide a crucial early warning that a projectile has been launched, as well as information on how to intercept it.

Europe is investing heavily to expand its ability to offer Ukraine this type of intelligence, but it still lacks some of the space-based systems that only the US can provide.

Kyiv’s reliance on American technology and support reemerged as a vulnerability in mid-October, when President Volodymyr Zelenskyy said Ukraine had not received the usual warning from allies of ballistic missile launches before a deadly attack on the country. Around the same time, sudden restrictions were reported on US government-controlled SpaceX satellite terminals that are an important part of Ukraine’s military communications.

Data from military satellites operated by Ukraine’s allies can show where Russian missiles and other airborne weapons are stored and commonly launched from. The Ukrainian military can use that information to strike at those facilities. The US and several European nations, including France, Italy and the UK, share their satellite intelligence with the Kyiv government.

However, only the US can offer near-constant space-based imaging of Europe. Its numerous and powerful spy satellites can provide higher-quality images, including video.

In a program called the Space Based Infrared System, or SBIRS, the US also has satellites in geosynchronous orbit, which keeps them over one spot on earth. These are the backbone of US early warning for missiles anywhere on Earth, and there is no equivalent in Europe. These satellites allow for real-time tracking of cruise missiles and other low-flying weapons that might escape detection by ground radar until it’s too late to stop them. This is especially helpful for a military, such as Ukraine’s, that relies on drones, aircraft cannons and other low-tech methods of destroying swarms of mass-produced projectiles.

Crucially, SBIRS can also detect the launch plumes of ballistic missiles. These missiles travel much faster and higher than other airborne weapons, making them harder to deal with. Knowing when a ballistic missile is fired, its speed and direction is vital for Ukraine’s air-raid warning systems. (An alert — even one that comes a minute or two ahead of the impact — can save lives by giving civilians time to take cover). That capability also gives Ukraine’s armed forces a greater chance of intercepting and destroying the inbound weapons.

It can be harder to knock out a missile at longer range. But a miss at long range still allows time for another shot. If an incoming missile is only noticed at the last minute, a miss at close range blows the final chance to foil a potentially devastating attack.

It allows Ukraine’s military to use Starshield, a military communications system that relies on Starlink, SpaceX’s low-earth orbit satellite network. Starshield is a US government-contracted service that’s distinct from SpaceX’s commercial Starlink broadband system. So Ukraine’s access to Starshield is ultimately contingent on the goodwill of the Donald Trump administration.

Starshield terminals allow pilots of Ukrainian interceptor drones and mid-range strike drones to control the machines. And frontline ground forces use Starshield terminals to coordinate supplies and movements along the front line. Starshield also supports real-time tactical intelligence gathering and communications, and has come to underpin the Ukrainian armed forces’ broader command infrastructure after terrestrial communications were badly damaged by Russian strikes early in the war.

SpaceX restricted the operation of Starshield terminals while in motion on Oct. 14 without telling Ukraine’s defense forces beforehand, according to a person familiar with the matter. The restriction immediately disrupted drone interceptions and mid-range strikes and hampered frontline logistics and reconnaissance. Zelenskyy accused both President Trump and Musk of intentionally throttling the service. Musk wrote on X, his social media network, that any limits on Starshield speed or usage “are decided by the US military and ultimately” the president. A senior US official said Trump didn’t order any limitations.

Europe’s militaries have a variety of earth-observation satellites that help Ukrainian forces locate Russian troops, tanks, artillery and military installations and identify ammunition depots, airfields and missile-launch facilities.

Finland’s ICEYE synthetic-aperture radar satellites can operate at night and see through cloud cover, smoke and haze. French satellite sensors detect thermal radiation and identify human activity that conventional cameras can easily miss.

Germany has paid commercial satellite companies such as US-based Planet Labs for high-resolution imagery for Ukraine, including inside Russian territory. This can provide data for targeting and spotting Russian military movement over time — potentially crucial intelligence that could thwart an attempted attack.

Europe is under heavy pressure to stop relying on the US for its defense, and military budgets in the region are growing again for the first time since the Cold War. A chunk of that new spending is going toward “strategic enablers” — communications and other systems that have an outsized impact on warfare despite not being weapons. European nations are racing to put more satellites in orbit and get more surveillance aircraft in the air.

ICEYE recently signed a deal with Nokia to develop a secure communications constellation for European defense and security. Airbus SE has for decades built satellites, and German defense giant Rheinmetall AG has also gotten into the game, including through a partnership with ICEYE. The European Union has begun launching the first of nearly 350 Iris2 secure communications satellites.

The pace of the rollout is limited, however, as the region does not have enough rockets with the power to launch heavy military satellites into orbit. Europe’s only sovereign heavy rocket booster is Ariane 6, which launches about 10 times a year from Kourou in French Guyana on the northern coast of South America. And European governments want to avoid using Musk’s SpaceX as they prefer to find their own way into orbit.

That would be a challenge. The US military launches new satellites regularly. Its Space Force plans more than a dozen flights in 2026. That gives the US a numbers advantage over any other country. The US has nearly 250 military satellites in orbit, compared with about 150 for China and about 100 for Russia. Many more are considered dual-use. Europe as a whole has about 50.

Besides imagery, US satellites can intercept communications and other transmissions — so-called “signals intelligence” that can also be used on the battlefield.

The US Space Force also announced in September that it had placed an operational weapon in orbit, although officials declined to say what sort of system it was.