In the event of a nonperpendicular crash with a movable object, like another car, between 20 and 30 mph, had the airbags deployed, they would have done more harm than good to you, and done more unnecessary and very expensive damage to your car. If you had been going, say, 45mph, then the airbags may have deployed. As mentioned before, they are designed to prevent your body and head from being thrown into the steering column or dashboard, and vice versa. They operated as intended, and you should probably be thankful they did not deploy in this relatively low speed crash. You are not alone, though, in misunderstanding the way airbags are designed to work. A couple years ago, my sister and her fiance were involved in a single vehicle accident. He fell asleep at the wheel, crossed over three lanes of traffic, sent the car airborne fifteen feet off the ground, and the car landed on its wheels in a field. This happened at 65mph. They walked away from the accident, but not without some minor injuries. Afterward, my sister was having a fit that the airbags didn’t deploy, and I had to explain to her as well that, in this kind of accident, the airbags would not have helped, and would probably have left them with more injuries. It takes serious frontal blunt force to get the airbags to deploy. I have heard something like 31mph to zero in an instant (like hitting a concrete wall) will deploy the airbags in most cars.