Not that Iran could build a large arsenal using this route rather than producing their own material. But the Iranians know that there is likely a red line that will prompt American and/or Israel to attack Iran's nuclear infrastructure (at least their infrastructure inside Iran). Crossing that line is dangerous and at that moment, Iran needs a maximum amount of deterrence. How could they do that?
One, they can keep their stockpile of threatening enriched uranium low enough to appear too small for weaponizing while they build up their ability to produce such material at a more rapid rate. Iran recently did this, earning them coveted stories about how their path to nuclear warheads is longer than once thought.
Two, they can get bombs using imported weapons-grade material to have ready before they can produce their own bombs. I assume North Korea is a source there. As was Syria before Israel bombed that reactor in Syria five(?) years ago.
For a price, anything is obtainable:
Despite years of effort and hundreds of millions of dollars spent in the fight against the illicit sale of nuclear contraband, the black market remains active in the countries around the former Soviet Union. The radioactive materials, mostly left over from the Cold War, include nuclear bomb-grade uranium and plutonium, and dirty-bomb isotopes like cesium and iridium.
The extent of the black market is unknown, but a steady stream of attempted sales of radioactive materials in recent years suggests smugglers have sometimes crossed borders undetected. Since the formation of a special nuclear police unit in 2005 with U.S. help and funding, 15 investigations have been launched in Georgia and dozens of people arrested.
Remember, we're dealing with fanatics in Iran--not idiots:
The problem from Iran's point of view is that they can't know if crossing one of these lines could trigger an American or Israeli preemptive strike out of fear that further delay in attacking would be too late to prevent Iran from getting nuclear weapons. And if I was an Iranian nutball, I wouldn't assume the Americans and Israelis couldn't knock out my infrastructure.
Were I an Iranian nutball, under those circumstances, I'd want at least a few atomic warhead on hand before I announce capabilities to produce atomic weapons-grade material. Which would mean I'd have had to have bought some from either North Korea or Pakistan--or possibly even from some broke custodian of Russia's arsenal.
If Iran can announce both the ability to make nuclear bomb material and the possession of actual nuclear weapons--perhaps by detonating one in a test on their own territory--Tehran would quite possibly deter an attack on Iran's nuclear infrastructure.
We're not dealing with idiots. If the Iranian mullahs believe there are red lines that trigger Israeli or American action, why wouldn't they take counter-actions rather than just blindly cross those lines and provide a pretext for military action against them?
Why do we assume Iran will race toward the objective of nuclear arms in the way most likely to be detected by us?
Have a super sparkly day.
