Air-defense systems have been tested in unprecedented ways in conflicts around the world by global military powers and smaller militant forces alike.

A missile launches from a US Navy warship in the Red Sea in February. US Central Command

From Ukraine to the Middle East, air-defense systems have been put under immense stress this year.
These big engagements show why it’s important for militaries to have a strong air-defense network.
They also offer the US military valuable lessons for a potential war with China in the Pacific.

Massive aerial assaults that occurred over the past few months have underscored the importance of having a robust, layered air-defense network to protect civilian and military targets from ballistic, cruise, and anti-ship missiles, as well as one-way attack drones.

The engagements offer the US military valuable lessons for a potential war in the Pacific, where a clash with China could feature thousands of long-range missiles and a demand for air defenses on a very large scale.

As engagements in Ukraine, Israel, and the Red Sea have shown, to be ready for such a daunting scenario, the US will need to substantially strengthen its air-defense capabilities in the region and produce more missile interceptors, former US Navy officers and air-defense experts say.

China has a “very large arsenal of very capable weapons,” Bradley Martin, a retired Navy surface warfare captain, told Business Insider.

“We don’t want to be in a battle of having to exchange missile-for-missile because we’ll run out much faster and it’ll be harder for us to come up with replacements.”

The need for air defense and the dangers of not having enough

Modern, game-changing technologies, like drones, have defined the Ukraine war, but decades-old air defenses have proven to be among the most valuable elements in an existential fight for Ukraine.

A Ukrainian air-defense system intercepts a Shahed drone mid-air above Kyiv on May 30, 2023. AP Photo/Evgeniy Maloletka, File

The war has shown how effective air defenses can be at denying air superiority, protecting key areas, and threatening high-value aircraft, as well as the costs when capabilities are degraded.

Ukraine’s air defenses, like its Soviet-era S-300s and US-supplied Patriots, have defeated enemy missile and drone strikes, hindered Russian air operations, and shot down numerous fighter-bombers and other Russian planes.

But in early 2024, as Russia was ramping up strikes, Ukraine’s network of air defenses capable of intercepting these attacks was stretched thinly as US aid remained stalled in Congress.

Ukraine rationed its defenses, moving them from the front lines to protect cities and other population centers.

As it ran critically low on interceptors, the lack of air defenses played a direct role in costing Ukraine the city of Avdiivka, as Russia gained brief and localized air superiority.

The impact has continued into spring 2024, as Russian bombardments continue and Ukraine’s defenses increasingly fail to intercept the attacks.

Ukrainian President Volodymyr Zelenskyy has repeatedly said additional air-defense systems were vital to keeping Ukrainian cities safe and protecting the front lines.

This week, he asked the US for more, requesting at least two more Patriots alone to protect Kharkiv, which is under heavy Russian fire.

Just last week, an overnight attack targeting Ukraine’s energy infrastructure included dozens of Russian missiles and drones.

In its assessment of the attack, the Institute for the Study of War think tank said “Russian forces will likely continue to conduct mass strikes to cause long-term damage to Ukrainian energy infrastructure as degraded Ukrainian air defense capabilities persist.” And that continues to be far from the only problem.

Firefighters put out fire caused by fragments of a Russian rocket after it was shot down by air-defense systems during an attack in Kyiv on May 16, 2023. Ukrainian Emergency Situations Ministry via AP

There are lessons for the US and its allies in this fight.

“If Ukraine is a guide, in a conflict NATO air defenses may down most drones and missiles, but some will get through,” experts at the RAND Corporation think tank wrote earlier this year.

“Ukraine and NATO might reduce risks with a two-prong strategy of strengthening air defenses and boosting infrastructure resilience.”

Testing air defenses in more places

Far from Ukraine, off the coast of Yemen, another air battle is taking place, as the Houthis continue to target ships transiting the Red Sea and Gulf of Aden, waterways facilitating global trade.

The Iran-backed Houthi rebels have fired on ships with one-way attack drones and anti-ship missiles — even making history by being the first group to use anti-ship ballistic missiles in combat. The group has struck a handful of merchant vessels, sunk one, and killed civilians on another. But many attacks have been defeated by Western navies.

US and coalition warships routinely shoot down many of these threats, defending both merchant vessels and themselves.

“What we did works, and it works well, and it does what it’s intended to do,” Archer Macy, a retired US Navy admiral, told BI. “Very few ships have been hit.”

A missile launches from a US Navy destroyer in the Red Sea in February. Screengrab/US Central Command

Among the systems in play is the Navy’s advanced Aegis Combat System, an automated and centralized weapons control system.

US destroyers and cruisers are equipped with this capability, which provides air and missile defense.

“The air-defense systems that the Navy has are very capable,” Martin, now a senior policy researcher at RAND, said, “and the type of layer defense that it tries to apply has been very effective.”

Aegis also came into play during the Middle East’s biggest air battle since the region descended into turmoil following Hamas’ Oct.

7 terror attacks against Israel. In mid-April, Iran and its proxies launched more than 320 cruise missiles, ballistic missiles, and one-way attack drones at the country.

American warships and a Patriot battery helped Israel’s Arrow systems down many of the ballistic missiles, while US, UK, and French fighter jets destroyed many of the drones. Altogether, around 99% of the threats were eliminated — a remarkable air-defense success.

Shaan Shaikh, a fellow with the Missile Defense Project at the Center for Strategic and International Studies think tank, said the engagement last month demonstrated just how effective a robust air-defense network can be.

“These systems work. We’ve seen in multiple campaigns now evidence of them working,” he told BI. “We’ve proven the technology at some degree, and I think that shows that this investment, in general, is worth it.”

An Arrow 3 ballistic missile interceptor is seen during its test launch near the Israeli city of Ashdod on Dec. 10, 2015. REUTERS/Amir Cohen TPX

But the supply of interceptors is insufficient. The US might not even have what it needs for an extended campaign against Iran. In the Pacific, Shaikh said, “China is going to be a whole separate ball game.”

China is a ‘different ballgame’

In a fight against China, the US would face a missile force unlike anything it’s fought before able to threaten US bases in South Korea, Japan, and Guam housing troops and aircraft, as well as US warships in strategic waterways.

Last fall, the Pentagon published its annual report on China’s military, documenting staggering increases in its long-range missile stockpiles and launcher numbers.

China’s arsenal of missiles, some with nicknames like the “Guam Express” and “Carrier Killer,” and the threat it poses are quite different from what is being seen in battles around the world right now.

Iran’s attack against Israel earlier this year was on a smaller scale than what might be seen from China, and the attack, although substantial, was not enough to overwhelm the defenses of Israel and its partners.

Chinese missiles haven’t been tested in combat, but Houthi threats appear far less sophisticated, with many of those failing as some Iranian missiles have and falling into the sea.

Chinese military vehicles carry DF-16 short-range ballistic missiles past Tiananmen Gate during a military parade to commemorate the 70th anniversary of the end of World War II in Beijing on Sept. 3, 2015. AP Photo/Andy Wong

The closest comparison is probably Russia, which has sophisticated missiles and the ability to launch large-scale attacks, but it’s “nothing like what we could see from” China, Thomas Shugart, an adjunct senior fellow with the Defense Program at the Center for a New American Security, said.

China could launch a preemptive strike that would leave American forces with little time to defend and potentially do serious damage. An attack could come on a tremendous scale that could overwhelm defenses. And a strike could come in waves.

A first wave could include hypersonic missiles fired at defensive systems, such as headquarters, radars, and missile defenses. Then, ballistic missiles could strike runways, trapping aircraft and preventing a quick response.

China’s arsenal affords it a number of strike options. The threat from China is one that demands air-defense solutions unlike any conflict seen today, a “very different ballgame in terms of scale and types of weapons,” Shugart said.

Needing more interceptors for the Pacific

From the fights this year, the US can see how it’ll need to employ air defenses in a potential showdown with China.

Shugart said he believes the real world, unscripted experience against the Houthis, as well as the data gathered from Ukraine shooting down Russian missiles, is giving American forces necessary lessons and experience that may be bad for China.

“The takeaway for these experiences might help us to prepare for dealing with something that’s a lot scarier,” he said.

A US Air Force B-1B Lancer assigned to the 37th Expeditionary Bomb Squadron takes-off from Andersen Air Force Base in Guam on Oct. 10, 2017. Staff Sgt. Joshua Smoot/US Air Force/Handout via REUTERS

To prepare for a conflict with China, the US will need a robust, concentrated combination of active and passive measures — ballistic missile defenses, systems like Patriots and Aegis, but also hardened bases, dispersed forces, runway repair crews, and mobile command centers, something that lawmakers sounded alarms on last week in a letter to US military leaders.

The military isn’t blind to the threat though.

“The sheer number of missiles that are out there today and that we’re seeing utilized in some of the more minor engagements is mind-boggling,” Air Force Lt.

Gen. Heath Collins, the director of the Missile Defense Agency said earlier this year. “We’ve got to be prepared for major engagements.”

Former Navy officers say it’s crucial that the US has enough air-defense interceptors to sustain an extensive missile fight in the Pacific.

That means it is important to produce more missiles like the SM-3, a capability that Secretary of the Navy Carlos Del Toro recently warned lawmakers would be needed in greater numbers to deter threats like China.

“Every time you engage something, you’re expending a missile, and after a while it starts to turn into a round-for-round calculation,” Martin said. “We would be using weapons at a much higher rate than we’re capable of replacing them.”

Ultimately, military leaders will need to consider how long air-defense capabilities will last when planning their campaign, said Macy, now a senior associate at CSIS’ Missile Defense Project.

This Dec. 10, 2018 photo shows the launch of the US military’s land-based Aegis missile defense testing system from the Pacific Missile Range Facility on the island of Kauai in Hawaii. Mark Wright/Missile Defense Agency via AP

Air defense alone can’t end a conflict, he said, but it can defend critical assets long enough that another force can end the threat by other means, like attack operations. Running out of air defenses before the enemy runs out of air threats spells trouble.

“We’ve demonstrated we can deal with a high-end threat, we can deal with the low-end threat,” Macy said. “It comes down to inventory.”