By Rebecca L. Grant, Ph.D., Vice President, Lexington Institute.
January 06, 2025 – The confusion over SM-3 highlights why the incoming Trump administration must pay closer attention to missile defense production priorities, as I wrote here for National Interest.
Yet just a few weeks earlier, President Joe Biden’s defense budget terminated production of that same missile in an attempt to budget release decision to “pivot from and discontinue” the SM-3 Block IB procurements in favor of the longer-range SM-3 Block IIA. In fact, these missiles are a matched pair with different capabilities needed by the Navy to operate in the harsh regime of exo-atmospheric defense.
Missile defense has not always been a high priority for the political or defense establishment in Washington. But the war in Ukraine, missile attacks on Israel, and the rising threat of China have gotten everyone’s attention. The confusion over SM-3 highlights why the incoming Trump administration must pay closer attention to missile defense production priorities.
The Standard Missile 3 clan specializes in the exo-atmosphere: the cold, dark, upper tier for missile defense and the perfect spot for intercepting and killing ballistic missiles. On Tuesday, another member of the clan, Standard Missile 3 Block IIA, became the first interceptor launched from Guam in a test proving capabilities to defend against potential Chinese attacks. After all, China’s DF-26 missile is chillingly nicknamed the “Guam Express.”
The two missiles, with their confusingly similar names, are not competitors; they are complementary interceptors, each with different ranges, designed to counter a wide array of threats from Iran and North Korea up to China and Russia.
Take the example of defending Israel. On April 1, 2024, Iran attacked Israel with a combination of 300 drones, ballistic and cruise missiles. SM-3 missiles were launched from destroyers USS Carney and USS Arleigh Burke in response.
Six months later, on the night of October 1, 2024, Iran launched approximately 200 ballistic missiles at the state of Israel. Ready and waiting were two U.S. Navy destroyers in the eastern Mediterranean: the USS Bulkeley and the USS Cole. Together, the ships launched a dozen missiles to intercept Iran’s barrage. The nose-on shots against incoming missiles proved the combat value of SM-3IB.
Both variants are needed for these demanding tasks, because they are specialized for distinct roles. SM-3 Block IB has a range of about 700 km. The SM-3 Block IIA has a larger second stage and a range of about 2500 km. However, while the SM-3 Block IIA has a longer range, it is not a replacement for SM-3 Block IB.
Here’s why. The SM-3 Block IIA defends a wider area, which is great for engaging a longer-range, more advanced threat set of medium and intermediate-range ballistic missiles. However, in other scenarios, that might allow the enemy to adjust which missile they launch, or they could try the tactic of depressing their missile trajectories, cutting into the effectiveness of SM-3 Block IIA. In contrast, the SM-3 Block IB, with its shorter minimum engagement range, provides U.S. forces with a complementary, increased engagement window. Missile defense tactics are complex, but this is why the U.S. Navy needs full stocks to deploy both SM-3 Block IB and SM-3 Block IIA together. Having both the SM-3 Block 1B and the SM-3 Block IIA missile interceptors available – in launch tubes on Navy ships, for example – gives the warfighter more time and the flexibility to engage with the most appropriate interceptor. By the way, that also improves magazine depth, a significant consideration during combat operations.
Deterring against coercive ballistic missile attacks is more important than ever. For example, the single Russian “Oreshnik” RS-26 intermediate-range ballistic missile with six Multiple Independently-targetable Re-entry Vehicles (MIRVs) was used against Ukraine on Nov. 21, 2024. Alarmingly, all six MIRV warheads evaded intercept.
The U.S. must keep the upper hand in the exo-atmospheric fight for its missile defense architecture to be effective. As great as Patriot and THAAD are, terminal defense alone isn’t enough for the threat landscape. Unconventional new weapons may detonate above terminal interceptor max ceiling heights. They can carry some bad weapons and warheads that need to be intercepted well before they get back into the atmosphere.
With threats looming, the Missile Defense Agency needs both variants of SM-3 and in sufficient quantities to make sure the Navy inventory never runs short.
This article was originally published on the Lexington Institute: https://lexingtoninstitute.org/two-navy-standard-missiles-divide-and-conquer-62-miles-up-from-national-interest/