From HSToday:

We all must agree that the elimination of terrorist events — domestic or international — is highly unlikely. There will always be a terrorist who succeeds despite our best efforts. We also have no control over when and where the next natural disaster will occur. So, logic dictates that if we can’t stop these disasters, than we must manage the consequences of them. This leads me to believe that the success of homeland security should be measured based on a community’s resilience. It’s not about preventing events, but rather ensuring that your community is equipped with what it needs to survive and recover from those events.