Has Iran lost its ability to make a nuclear bomb after the US strikes?

It would be sensible to wait until the dust has settled before judging whether the US strikes on Iran were, in Donald Trump's, words, "a spectacular military success".

And when dropping bombs that weigh more than 13 tonnes each, there's going to be a lot of dust.

The US claims to have struck Iran's three largest nuclear facilities.

Follow latest: Iran considering 'all options' after US strikes

Perhaps the most important is the Fordow complex, buried deep in a mountain near the city of Qom - it was the only one not previously damaged by Israeli strikes over the last few days.

The claim by the US that it dropped at least six of its largest GBU-57 bunker buster bombs on Fordow is telling.

Despite their size, it was known that one of them would be insufficient to penetrate 80+ metres of solid rock believed to shelter Iran's most sophisticated uranium enrichment technology deep within Fordow.

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It seems the US used their bombs to target the mountain stronghold's three entrances - at least that is what Iranian state media appears to be claiming.

The idea is to rely on the significant shockwaves generated by the blasts to destroy infrastructure within and, at the very least, entomb the facility, rendering it useless. For now, at least.

If nuclear facilities at Isfahan, Natanz and Fordow were "obliterated" as Donald Trump has claimed, or even crippled, it would certainly halt Iran's ability to enrich the uranium needed to make a viable nuclear weapon.

But that's not the same as preventing Iran's ability to make a nuclear bomb.

To do that, they need "weapons-grade" uranium; the necessary metal-shaping, explosives and timing technology needed to trigger nuclear fission in the bomb; and a mechanism for delivering it.

The facilities targeted in the US raid are dedicated to achieving the first objective. Taking naturally occurring uranium ore, which contains around 0.7% uranium 235 - the isotope needed for nuclear fission - and concentrating it.

The centrifuges you hear about are the tools needed to enrich U-235 to the 90% purity needed for a compact "implosion"-type warhead that can be delivered by a missile.

And the reality is Iran's centrifuges have been spinning for a long time.

United Nations nuclear inspectors warned in May that Iran had at least 408kg of uranium "enriched" to 60%.

Getting to that level represents 90% of the time and effort to get to 90% U-235. And those 400kg would yield enough of that weapons-grade uranium to make nine nuclear weapons, the inspectors concluded.

The second element is something Iran has also been working on for two decades.

Precisely shaping uranium metal and making shaped explosive charges to crush it in the right way to achieve "criticality", the spark for the sub-atomic chain reaction that releases the terrifying energy in a nuclear explosion.

In its recent bombing campaign, Israel is thought to have targeted facilities where Iranian nuclear scientists were doing some of that work.

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But unlike the industrial processes needed to enrich uranium, these later steps can be carried out in laboratory-sized facilities. Easier to pack up and move, and easier to hide from prying eyes.

Given that it's understood Iran already moved enriched uranium out of Fordow ahead of the US strike, it's far from certain that Iran has, in fact, lost its ability to make a bomb.

And while the strikes may have delayed the logistics, it's possible they've emboldened a threatened Iran to intensify its warhead-making capability if it does still have one.

Making a more compact implosion-based warhead is not easy. There is debate among experts about how advanced Iran is along that road.

But if it felt sufficiently motivated, it does have other, less sophisticated nuclear options.

Even 60% enriched uranium, of which - remember - it has a lot, can be coaxed to criticality in a much larger, cruder nuclear device.

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This wouldn't pose as much threat to its enemies, as it would be too heavy to fit on even the best of Iran's long-range missiles.

But it would, nonetheless, elevate Iran to the status of a nuclear power.