Airports: Are They Safe?

Today at LAX airport on Los Angeles a TSA agent was shot dead by an attacker inside the airport. This morning a man identified as Paul Ciancia entered the airport and opened fire with has automatic rifle on any TSA agent he could find. Ciancia ended up only killing one agent but injured at least three more. Today marked the first time a TSA agent was killed while on duty since the creation of the agency. 

With all of the added security at airports nowadays it seems to always be expected that it is a safe as can be inside. Yet, today it showed that even when inside it is not as safe as we think. Ciancia was able to conceal his weapon and his over one hundred rounds of ammounition just by putting into a traveling bag. Once inside he was able to quickly take it out and open fire. Even though Ciancia did not get to a plane with his weapon or into the heart of the airport he was still able to do the damage that he wanted to do. 

Are airports as safe as we think? Is an addition to security screening necessary? Are Americans becoming over worried when this is the first time an agent has been killed in the twelve years the agency has been operating? Shar your thoughts.