Control of space will determine security in this century in the way that control of the seas did in the nineteenth and control of the air did in the twentieth, the Defence Secretary will say today in a keynote address to the first UK Space Power Conference.

Wes Streeting is due to address the conference as the Royal Air Force announces the formation of No. III Space Effects Squadron, its first unit dedicated to disrupting, degrading and denying hostile activity in orbit.

He will say: “Britain has to keep pace in the new space race. Control of the waves was the essential ingredient in 19th century deterrence. That is why Britain built the finest naval power in history. In the 20th century it was control of the skies, and so we built a world class air force to protect us. This century will depend on control of space.”

On why the domain has become contested, he will say: “Our dependency on space is precisely why it is increasingly under threat from our adversaries. That threat is growing in scale, speed, and sophistication. And challenges in space increasingly mirror the geopolitics on Earth.”

Setting out what he takes his own responsibility to be, he will say: “My job is to make sure that our deterrence in space is as strong as it is on Earth, and to modernise our armed forces so that they are ready to deter and, if necessary, defeat any adversary, in any domain.”

The comparison he draws carries an implication about scale, given that Britain built the Royal Navy and then the Royal Air Force as the principal instruments of national defence in their respective eras, and applying that logic to space invites a question about how large a space force the argument requires, against current investment of £880 million between 2026/27 and 2029/30 in space-based intelligence, surveillance and reconnaissance and space control activities.

That sum forms part of the £7.8 billion committed to space until 2030 in the UK Space Strategy published earlier this month, of which more than £3 billion is directed at defence capabilities in orbit. The strategy also allocated £2.8 billion towards connectivity including the SKYNET military satellite communications programme, and £149 million to the European Space Agency’s Vigil mission alongside £85 million for the National Space Operations Centre.

Streeting said at the time that national security depends on freedom of action in space and, if necessary, the ability to protect British and allied space assets, and that as threats in orbit grow more sophisticated so must the ability to detect and respond to them.

The Strategic Defence Review stated that the ability to operate in, from and through space underpins British security, prosperity and daily way of life, and the department says challenges in the domain increasingly mirror those on Earth as hostile states develop capabilities to jam, disrupt or disable space assets.

Britain has formally ruled out destructive anti-satellite missile testing and continues to work through the United Nations Committee on the Peaceful Uses of Outer Space on norms of responsible behaviour in orbit.