The US will attack Iran because of its position in the oil rich middle east and because of lobbying by Israel.
It will make up some lies about Iran having WMD and then they will have an Iranian speak to congress about Iranian soldiers throwing babies out of incubators like they did twice before, just before each of the wars on Iraq. Two people making exactly the same speech and in the case of the girl used the second time it was shown that she has never been to Iraq.
But none of this will matter
The US public is incapable of seeing the blindingly obvious truth if its government says differently
For those who are interested here is a good account of how the US people get suckered into supporting wars
http://whatreallyhappened.com/WRHARTICLES/incubatorlie.html