T-Dome: Look for the budget, not the statements

Taiwan’s announced ambition to build a comprehensive air defence system called T-Dome will depend entirely on funding. Taiwan will need deep pockets to repel a Chinese attack, and this needs to be built in from the start. 

On Friday October 10, Taiwan’s President Lai Ching-te gave a speech celebrating the country’s National Day, he set out plans for increased defence spending and the goal to build the T-Dome. “We will accelerate our building of the T-Dome, establish a rigorous air defence system in Taiwan with multi-layered defence, high-level detection, and effective interception, and weave a safety net for Taiwan to protect the lives and property of citizens,” Lai said, according to Reuters. 

Israel’s air defence network provides some indication of what would be involved for Taiwan’s T-Dome, and is worth considering. The Israeli system is layered, consisting of the short-range Iron Dome air defence system, mid-range David’s Sling, Patriot systems, and the Arrow-2 and Arrow-3 systems, which are designed to intercept ballistic missiles inside and out of the Earth’s atmosphere. More recently, the Israeli Defence Force added the Iron Beam 450 laser system to its arsenal to complement its short-range capabilities. All of this is coordinated and supported by command and control systems and there are strategic radars and space-based systems providing additional detection and surveillance. 

This type of arrangement is essential when a comprehensive air defence capability is the goal, and it is important to note that when Iran exerted the greatest pressure on Israel, the US brought Arleigh Burkes with their very capable Aegis air defence system to the region, as well as THAAD ballistic missile defence systems to the region. There were five Arleigh Burkes in the Eastern Mediterranean from June 2024, and they intercepted several Iranian missiles. The THAAD systems deployed by the US fired more than 150 missiles, which is potentially 25% of all THAAD interceptors ever built at the time.

At present, Taiwan’s Air Force has seven Patriot batteries and 12 Sky Bow III batteries on order, which can provide some terminal defence against ballistic missiles and good interception rates against cruise missiles and drones. It has also ordered additional PAC-3 systems and PAC-3 MSE missiles. Its aircraft are also relatively well-equipped with air-to-air missiles, which would also be important in defending against China. The Taiwanese Army deploys a number of short-range air defence systems and the Land Sword (TC-2) mid-range systems, which are based on the Sky Sword air-to-air missile. 

Taiwan’s Navy has a nascent air defence capability, which is being improved through domestic production of a Mk 41 vertical launch system and variant of the Sky Bow III missile. The total numbers of ships to carry these systems are unclear, but could conceivably contribute to the island’s defence. More recently, Taiwan revealed that the Tiang Kung (Strong Bow) ballistic missile defence system was in service. It is understood to provide mid-course interceptions against tactical ballistic missiles like China’s DF-11, which has a range of 600 km, according to CSIS. 

So, the evidence suggests that Taiwan is already investing in the systems needed to make the T-Dome a reality. Having more air defence launchers is helpful, but only part of the battle. The key metric for air defence efficacy is the interceptor stockpile, and the ability to replenish it. And this is really where the budget becomes key. China has a range of long-range strike options, and with the Taiwan Strait being just 130 km at its narrowest, this would include PHL-16, a multiple rocket launcher capable of firing up to eight 370 mm Fire Dragon guided rockets out to distances of 220 km, or a single ballistic missile up to 500. In addition to this, the PLA Rocket Force has its own suite of short-range ballistic missiles, as well as medium-range and intercontinental missiles. Its mission is subject to some debate as it would certainly play a role in deterring or engaging US forces. However, it is probable that it would contribute to any military action against Taiwan, having already fired missiles over the island during exercises. 

The PLA Air Force and PLA Navy are armed extensively with subsonic cruise missiles, which would enable them to attack land and maritime targets from within Chinese airspace, as well as from the opposite side of Taiwan, which would further complicate the air defence picture. China also has an automated factory, which is claimed to be capable of producing a thousand components for cruise and anti-ship missiles per day. The veracity of this claim must be treated with caution, but if China could even produce 100 strike missiles per week, the challenge for Taiwan would be the same, albeit at a different scale. 

That challenge is that, generally speaking, the attacker in an air defence scenario has the advantage. Using the example of Israel above, deafening against 12 days if Iranian strikes – which can be assumed to be fairly benign compared to what the People’s Liberation Army would attempt – cost at least $1 billion in interceptors. This is to say nothing of the depletion of US stocks of missiles that are slow to reproduce. Take the PAC-3 MSE for example, which is a good option for cruise and ballistic missiles. Lockheed has recently stated that it is on track to produce 650 of these missiles per year for Patriot users. This is good and welcome news, but those missiles are for customers around the world, including the US. They would not all be focused on a single user, and it is possible to see a scenario in which China could deploy 600 ballistic missiles against Taiwan in a matter of weeks. 

The challenge for Taiwan is therefore to produce and stockpile (and protect) enough interceptors to deter a Chinese attack. And possibly to survive one for long enough for the US to intervene and alter the balance of power and targeting rationale. This is a serious investment, likely requiring billions in missile procurement and production over the next few years. As a benchmark, CSIS estimates that a new Patriot battery with missiles costs $1 billion, of which $690 million is the missiles alone. A PAC-3 MSE can cost $4 million per shot, and it is common to fire two per intercept. The costs are significant, and Taiwan is thought to have at least 200 PAC-2 and 380 PAC-3 Cost Reduction Initiative missiles in its stockpiles, but that is unlikely to be enough.

There may be ways to reduce those costs, and Lockheed executives have indicated that reducing the required shelf-life of the missile and its components could be one option. Even so, an effective defence of Taiwan against China would likely require thousands of air defence interceptors, possibly over many months. That is why the budget proposal in 2026 and ongoing support for the T-Dome will be key to the programme’s success and utility. If it is not properly resourced with interceptors, then the investment is unlikely to achieve the desired results.

By Sam Cranny-Evans, published on October 10, 2025. The lead image shows a Patriot launcher, it is similar to the systems that make up the bulk of  Taiwan’s air defence capability. Credit: Lockheed Martin.