Barack Obama made what ought to have been a completely innocuous statement yesterday:
"Iran, Cuba, Venezuela: these countries are tiny compared to the Soviet Union. They don't pose a serious threat to us the way the Soviet Union posed a threat to us. And yet we were willing to talk to the Soviet Union at a time when they were saying we want to wipe you off the planet. (...) Iran, they spend one one-hundredth of what we spend on the military. I mean, if Iran ever tried to pose a serious threat to us, they wouldn't stand a chance."
John McCain decided to take exception to this:
"Senator Obama claimed that the threat Iran poses to our security is "tiny" compared to the threat once posed by the former Soviet Union. Obviously, Iran isn't a superpower and doesn't possess the military power the Soviet Union had. But that does not mean that the threat posed by Iran is insignificant. On the contrary, right now Iran provides some of the deadliest explosive devices used in Iraq to kill our soldiers. They are the chief sponsor of Shia extremists in Iraq, and terrorist organizations in the Middle East. And their President, who has called Israel a "stinking corpse," has repeatedly made clear his government's commitment to Israel's destruction. Most worrying, Iran is intent on acquiring nuclear weapons. The biggest national security challenge the United States currently faces is keeping nuclear material out of the hands of terrorists. Should Iran acquire nuclear weapons, that danger would become very dire, indeed. They might not be a superpower, but the threat the Government of Iran poses is anything but "tiny.""
As McCain noted, Obama said that the threat posed to us by Iran is tiny compared to the Soviet Union. And guess what? It is. There are lots of ways to measure this. The best figures I could find for Iran are from 2004 (pdf); for the USSR, I'm using figures from 1988. In 2004, Iran had 540,000 people in its active military; in 1988, the USSR over five million. Iran had 1565 main battle tanks; the USSR had over 53,000. Iran had 306 total fixed-wing aircraft in 2004; the USSR had about 6,660. Iran had three submarines (who knew?); the USSR had 360. Iran had over 250 major SAM launchers; the USSR had over 9,000. And that's not even counting things like satellite systems.
However, by far the most important threat that either the USSR or Iran could pose to the US involves nuclear-armed bombs and missiles. Both Iran and the USSR are separated from us by oceans, and whereas parts of the USSR are pretty close to Alaska, no part of Iran is less than five thousand miles from the US. In order to threaten us, Iran would have to rely heavily on either aircraft (see above) or missiles, and by far the worst threat any country could deploy using either would be nuclear weapons. Moreover, each and every nuclear weapon that was detonated in the US would reduce the surrounding area to radioactive glass. During the Cold War, the USSR had thousands of ICBMs, many of which were pointed straight at us. Just look:
Here, for comparison, is the analogous chart for Iran. It includes not just nuclear warheads, but all nuclear weapons of any kind:
Besides the number of nuclear weapons Iran possesses, there's also the matter of delivery systems. Iran's current missiles do not even reach most of Saudi Arabia, let alone the USA. I don't know how good its three hundred-odd fixed-wing aircraft are at refueling in flight, but they would have to be to pose a threat to us: I sincerely doubt that any European countries would let Iranian bombers refuel en route to the US.
Tiny, compared to the USSR? We report; you decide.
Note also that Obama was talking about the threat posed to the US. That it poses a threat to Israel is a different matter. (When we discuss this threat, it would be a good idea to remember that Israel already has nuclear weapons, as well as a much better army.) Iran's IEDs do threaten our troops in Iraq, but: (a) this threat, though bad, is tiny compared to the threat of thousands of nuclear weapons aimed at the US, and (b) Obama has, and McCain lacks, a plan to get our troops out of harm's way.