Iran stands accused by the US of developing nuclear weapons, supporting global terrorism and insurgents and Afghanistan, and occasionally of suppressing democracy and human rights at home. How important are these in US policy do they genuinely drive Dick Cheney's manoeuvrings? What of Iran's new alliances with Russia and China, which have a significance far beyond Central Asia?
Iran's nuclear programme is a genuine source of concern, a potential threat to the aims of non-proliferation.
But the problem is that the West is demanding that all manufacturing of nuclear fuel is internationalised before global moves are made to ban nuclear weapons and wind down nuclear power, with massive investment in alternative energy sources.
Hypocritical commands to Iran will eventually fail, and Washington knows this.
Support for Hezbollah, Hamas and `insurgents' is clearly a response to what is perceived as injustice and dominance by Israel and the US. There are solutions to this, which include negotiated solutions. Such a strategy would weaken radicals within the Tehran regime.
A quick review of other factors explain US policy.
1. The US is goaded by the ideological defiance of Iran to the US and its influence in the region;
2. Iran, Hezbollah and Hamas are strong magnets on the Middle East street for those with hatred of Israel and the US.
3. Iran presents a model that challenges the western secular capitalist agenda and has some attraction across the region.
4. The Iranian revolution 28 years ago overthrew a close US ally (the Shah) and then humiliated the Americans by taking diplomats hostage.
5. There's always the issue particularly close to Cheney's heart - oil - Iran has the world's second largest reserves of oil and gas.
6. And then there's the habit of projection. The US is driven more than most by an ideology of “realism” - power through military strength. He who lives by the sword...
The new danger
But there is a particularly acute reason for the Americans to be focused upon Iran.
China, Russia and the Central Asian states have been busy building a new strategic alliance called the Shanghai Cooperation Organisation (SCO), with Iran, India and Pakistan as observers.
They have had joint military and security exercises, and are starting to collaborate over energy policies.
Iran is now China's largest supplier of oil, oil that is critical to China's growth plans. The SCO has already told the US to wind down its presence in Central Asia, and many American strategists are profoundly worried for the wider implications, now that the US has been so weakened by its experience in Iraq.
Oil-rich Iran could be the front line in a new Great Game, and if we are not careful, a new and perhaps hotter Cold War.