How the US Navy’s space weapons helped to defend Israel against Iran’s ballistic missiles

Yesterday evening, as Iranian missiles rained down on Israel, there was an interesting maritime development. Three US Navy Arleigh Burke class destroyers closed the coast of Israel and fired interceptor missiles, over land, to help defeat the incoming Iranian threat.

The Pentagon statement simply said that 12 missiles were fired from two destroyers, USS Cole and USS Bulkeley. USS Arleigh Burke, name ship of her class, was also there but not named in the initial press release. As tends to be the way, this has led to a raft of speculation as to what weapons fired and how successful they were. I have to admit to an intense interest in the matter, as a former anti-air warfare specialist in the Royal Navy.

One thing to bear in mind is that warship capabilities are kept at the highest end of Secret. Much can be gleaned online from manufacturers’ leaflets and the odd leaky sailor, but only a very few know how this sort of thing works in practice. HMS Diamond proved in the Red Sea that even the captain and ship’s company didn’t know the capability of some of their systems until they used them for real. Manufacturers’ figures, simulations, and tests against simple targets that fit within the budget only get you so far – there is no better way to evaluate complex systems than doing it for real.

The number 12 for missiles fired is interesting. An Arleigh Burke destroyer has either 90 or 96 Mark 41 vertical launch cells, into which a variety of missiles can be put: various kinds of Standard Missile (SM-2s, SM-6s or SM-3s), Tomahawk cruise missiles, ASROC anti-submarine torpedo carriers and various other things.

The SM-3 is probably the interesting one here, however. Unlike all the others it is a space weapon: it carries an Exo-atmospheric Kill Vehicle (EKV) rather than a normal warhead. An EKV is lobbed out of the atmosphere by the launching rocket, and then, if it has been sent to the right general area of space, it can acquire a ballistic missile warhead coming towards it using its onboard telescope system. It then uses its thrusters to get exactly in the way of the warhead, so that the incoming enemy weapon crashes into it and is destroyed – by its own kinetic energy, as much as that of the EKV.

That may sound fanciful, but it can work. An SM-3 was used by the US to shoot down one of its own malfunctioning spy satellites above the Pacific back in 2008: and the system has been enhanced significantly since then.

As you’d imagine, however, the SM-3 is one of the more expensive things you might put in a vertical launch cell at $11m a shot. I hear that an Arleigh Burke destroyer will typically have just six of them. But in the case of last night’s attack, the SM-3 would be the only really useful weapon for US warships on the other side of the target nation from the aggressor. I’m going to speculate that the Cole and the Bulkeley may have shot away their SM-3s last night, and probably whittled down the incoming ballistics significantly. But it’s speculation: other weapons may have been in play.

One thing I do know is that putting a warship that close to land (inside an enemy anti-ship missile envelope, one should note), and being part of an air picture compilation effort sufficiently detailed to be able to fire hundreds of miles inland is quite remarkable. To compare, I was the air warfare officer in an old Royal Navy Type 42 destroyer in 2005 and our missile system – the by-then fairly ancient Sea Dart – had a maximum effective range of forty nautical miles, no overland capability (in either the missile or the radar) and the target had to be heading pretty much towards you. Operating alongside an Arleigh Burke back then made you feel like you’d brought a knife to a gunfight. Or perhaps a rock.

Perhaps even more impressive is how the American Aegis combat system (used in both its Arleigh Burke destroyers and its Ticonderoga class cruisers) has since got better and better. The USS Cole which shot ballistic-missile interceptors over land and into space last night bears only a cosmetic resemblance to the same ship that was struck alongside in Aden in 2000 by a suicide boat, killing 17 American sailors. The US Navy hasn’t forgotten that day, though, and in some quarters there will be a sense that last night a point was made.

There are lessons for Britain here as we start to think about our own ballistic missile defence systems. In principle, in the Type 45 destroyer, we already have one. In reality, we didn’t build enough of them and they will need upgrading before they can tackle really capable ballistic threats. The day when we have our own SM-3 equivalent is far off: our current French-made Aster missiles are not in the same league.

As to ‘what next’ in the Middle East, we will have to wait and see. I got close to the planning for this sort of thing not that long ago and can say a couple of things for certain. First, going after Iran’s nuclear capability is something Israel has wanted to do for decades but they haven’t done it: because it’s hard, and because the Hezbollah missile arsenal in Lebanon – close by and able to hit Israel much harder than Iran itself can – remains mostly unused.

Israel says it will now hit Iran but I think that oil infrastructure is a more likely target (and easier) than nuclear. The caveat here is that anything that drives up the price of oil just before the US election will not be popular over there. But Israel could do this one on its own.

For now, it’s hats off to the US Navy ships in the Eastern Mediterranean that were involved last night, and old Middle East veterans like me will be especially glad to see USS Cole getting some rounds off. It was an expensive display of capability but then warfare is rarely anything else.

Many other ships are poised out there, including our HMS Duncan, ready for the ‘what next’, which will take shape over the coming days and weeks. In the meantime, we Brits should expedite the unlocking of the Type 45’s latent ballistic missile capability and agree quickly on a replacement that can contribute to the missile protection of the UK.