Such is the speed and significance of the ISIS advance, it is forcing together old enemies, America and Iran, to try to help the Iraqi government. .
Tentative talks between the two countries have been arranged.
Does this suggest that America has run out of options on Iraq?
ITV News Washington Correspondent Robert Moore has been finding out:
The Foreign Secretary has been clear on the threat of Isis, but he has ruled out the prospect of any UK military involvement in the crisis.
Iraq’s foreign minister, Hoshyar Zebari, is a natural diplomat. Polite, immaculately dressed, and blessed with a great memory.
Isis has paraded military equipment in Mosul it captured from when the Iraqi army fled in what some see as a "nightmare scenario."