Several days to decide? This is big-budget governance: there should already be a binder on the shelf (amid thousands of other what-if plans & playbooks) marked “Al Qaida Moves To Seize Iraq”, open it and proceed accordingly.
Except he already is! He planned to stall while AQ moves fast to take over before opposition can start.
He is telegraphing to ISIS that they are free and clear to march onward without any resistance from the US.