MAKE THE RUBBLE BOUNCE PRODUCTIVELY.

Iran's efforts to build something under a granite mountain came to the attention of United States military planners long ago, as did the efforts of another country.

The 509th's raid was three decades in the making. In 1996, the U.S. experimented with deep penetration conventional bombs and timing attacks so the second bomb struck milliseconds behind the first. A second bullet in the first bullet hole, one-two punch. In September 1996, I wrote a column mentioning the tests. The potential target: Libya's chemical weapons stash hidden under a mountain. The 509th's MOPs delivered these one-two punches.

The timing of those punches is important.

There are real limitations to how deep you can get into rock when you plunge something into it.

It’s very interesting to have gone from that background, that computational background, to standing over such a hole that had been blown into a mountain. One of the things that has been discussed is, can you do what they call multiple miracles – sequential miracles? If you can drop a weapon – if you’ve got three B-2s up there – and they each drop a weapon that can vector itself to a very highly accurate position in a mountain, and you can penetrate with one and blow a hole, and then all of that material is suspended. And you have another one come in immediately afterwards and penetrate through much softer material, until you get into hard material, and you penetrate that, and then you explode, and you levitate all that material. Then you bring a third one in after it, you could start thinking about digging really deeply in. Now, I’ve got no idea whether this operation, Midnight Hammer, I think, is the term that was used, whether that was such a sequential process with that kind of accuracy [it was, each hole got six MOPs]. But, gee, that’s awesome, to be able to have subsequent devices, avoid the blast of the previous ones, and yet penetrate in and, like a sledgehammer, drive through again and again into a harder material.

The point of using a shovel to dig a hole is to move the material from inside the hole to outside the hole.  Not so easy when you're using a weapon sort of like a pile-driver, particularly because the rubble in the hole will fall to the bottom of the hole that you're trying to dig deeper.

You’re surely going to have suspended material. But if you can avoid the shock from the initial explosion for the second and third penetrators – you know that that is really highly, highly tuned delivery, and we have gotten very good now. I’m not saying that I know anything about that. I’m just saying that that was part of the discussion during the time that I was working on it, could we actually do these sequential miracles and get these things on target? And when we watch Elon Musk land rocket ships, we go, maybe we’re in that kind of a world.

If I remember the logic of dense-packing missile siloes correctly, the point was to make life difficult for warheads arriving not-quite-simultaneously, such that the blast debris from the first hit ruins the effectiveness of subsequent hits.  With the burrowing bombs, there's a similar challenge, which, apparently, if you can get each of the following bombs into the hole the first one started digging before the dust settles from the preceding explosion, without the preceding explosion disrupting the performance of the following bomb, allows a sequence of bombs to dig down to where the target is.  It's not as easy as dropping something really heavy from an altitude at which a high terminal velocity is possible.

If you just have a solid piece of tungsten, and you deliver it at infinite velocity, would it go all the way through the Earth? And the answer is no, it would go a certain depth, and then would stop. Even if it was solid tungsten, three feet in diameter and 30 feet long, there is going to come a point where it’s going to lose all of its momentum, and that energy will be dissipated into sort of a half sphere. So understanding that there are limitations to penetrators, and there are limitations to what kind of forces, shock forces that the explosive package can tolerate, is part of the question.

It appears as though the penetrating bombs deployed in Operation Midnight Hammer worked as the designers intended.  "Was the Iranian program 'obliterated'? Argue about the word if you like. But the damage inflicted by the U.S. and Israeli attacks appears to have been devastating."  We'll conclude with what could otherwise be a Friday short take, but with that post taking on monumental proportions, it goes here.  "There’s an easy way for Iran to avoid further bombings: Stop trying to build nuclear weapons."