War at the Speed of Light: The Emerging Role of Directed-Energy Weapons

For decades, notions of laser weapons have been the stuff of science fiction. Now they are becoming military reality, as directed-energy weapons, including high-energy lasers and high-power microwave weapons, open new approaches to counter swarms of cheap drones.

Technical challenges need to be resolved before directed-energy weapons can become operationally effective. For example, atmospheric effects can reduce the effectiveness of high energy lasers, and the heating of atmosphere layers by the energy of the laser beam can lead to a phenomenon called ‘thermal blooming’, which reduces the energy of the beam. There is also a requirement for sustained and ample power generation to ensure that directed-energy weapons can maintain destructive power or enable rapid shifting of a weapon’s beam across multiple targets. Furthermore, directed-energy weapons are short-range, line-of-sight weapons and thus are largely limited to defensive roles.

Meanwhile, the challenge to defeat swarms of cheap drones, typified by Iran’s Shahed series used in both the 2026 Iran war and by Russia against Ukraine, demands cheaper and sustainable defensive systems – and using directed-energy is much cheaper than firing missile interceptors.

Adversary states such as China also recognise the importance of directed-energy weapons. In early February, China unveiled a 20-gigawatt power source for a high-power microwave weapon that can threaten U.S. Starlink satellites in orbit. China also displayed its LY-1 laser weapon to defend warships against drones during last year’s Victory Day parade.

Certainly, directed-energy weapons may be key to inexpensively countering missiles and drones, but technical limitations prevent them from completely replacing traditional military systems. There will still be a need for long-range interceptor missiles such as Patriot and Thaad for over-the-horizon air and missile defence, because directed-energy weapons cannot generate effect beyond a visual line of sight. High-power microwave weapons can be used offensively alongside electromagnetic warfare, in what might be described as ‘electromagnetic operations’, but without massive power supplies they too are short-range weapons.

In considering how directed energy might be used operationally, particularly for future employment by the ADF, two key roles emerge: defending fixed installations against drone and missiles; and defending naval vessels at sea. Directed-energy weapons would complement more traditional air and missile defence systems in such roles.

The report explores current efforts towards developing directed-energy weapons. It notes that the 2024 National Defence Strategy and its accompanying spending plan, the Integrated Investment Program, identify directed energy as one of six defence innovation, science and technology priorities. Directed energy is also mentioned as a possible area of capability development in project Land 156, which seeks to develop or acquire a system for protecting critical military and civilian infrastructure against cheap drones.

With the 2026 NDS and IIP due to be issued on 16 April, it’s time for Defence to move more decisively towards embracing a directed-energy capability for the ADF. Australian companies are developing both high-energy lasers and high-powered microwave weapons (also referred to as radio-frequency weapons) suitable for countering cheap drones, both ashore and at sea.

The report argues that it is important for Defence to develop a directed-energy weapons strategy that would provide a framework for accelerating development of this technology and ensure its timely integration into the force structure. Australian defence industry companies need to fully support sovereign directed-energy development through continuous modernisation processes. The strategy should also emphasise building opportunities for collaboration on directed energy through AUKUS Pillar Two and with partners such as Japan and South Korea. Such a strategy should recognise the opportunity for Australia to lead in the development and testing of directed-energy weapons, including by exploiting its natural geographic advantages and technology-driven economy.

Malcolm Davis is a senior analyst with ASPI’s Defence Strategy program.

AI contributed no ideas to this article – Malcolm Davis.

This article appeared originally at The Strategist (ASPI).