It took a CBS News crew more than 14 hours to drive south from Turkey to Tehran, a nearly 600-mile trip made longer by checkpoints and bad roads.

With questions mounting over the impact of the U.S. and Israeli onslaught on Iran's nuclear facilities and military infrastructure, a return to hostilities could be a matter of when, not if.

The fragile ceasefire between Israel and Iran appeared to be holding after a rocky start, giving rise to cautious hope that it could lead to a long-term peace agreement.