>> people forget how different the world was when the bombing happened. and i think it shattered across the world people's feelings of safety and security because if it can happen in oklahoma city, it can happen anywhere. if it can happen to me, it can happen to anyone. >> we became a more cautious society, barriers went up around federal buildings. you have more security. the seeds of homeland security were actually planted by timothy mcveigh. >> there were other changes, as well. the attack led to significant engineering improvements that allow buildings to better withstand excessive forces, whether manmade or natural. and legislation passed in the wake of the disaster has given greater voice to the victims and families left behind by attacks like the oklahoma city bombing.