It's quite credible, but I wouldn't bet too much on it.
Most likely, car bombs in highly populated areas, but not too many. If it was a massive attack, then you would need to fear. I am not afraid of a few car bombs. What I do fear is a massive invasion, multiple attacks, actual terrorists attacking and murdering everyone in sight. That would be a worst case scenario.
Still, not gonna happen. If there is an attack, there is one. If it happens, it happens. Nothing you can do. I'll be sitting at home on reddit either way, and if there is anything to fear about, I'll go crawl into my corner and cry. While on reddit.