In light of the five year anniversary of September 11^th, many are asking the question, "Are we safer?" President Bush gave a speech on that subject in Atlanta this past Thursday, September 7, 2006. He said:

Many Americans look at these events and ask the same question: Five years after 9/11, are we safer?

The answer is yes, America is safer.

(APPLAUSE)

We are safer because we've taken action to protect the homeland. We are safer because we are on the offense against our enemies overseas. We're safer because of the skill and sacrifice of the brave Americans who defend our people.

Six months after September 11, 2001, the White House announced the creation of the Homeland Security Advisory System. Per the press release on the matter:

We, too, must take new measures to protect our cities, our resources and people from the threat we face today, the threat of terrorism. That is why today we announce the Homeland Security Advisory System.

The Homeland Security Advisory System is designed to measure and evaluate terrorist threats and communicate them to the public in a timely manner. It is a national framework; yet it is flexible to apply to threats made against a city, a state, a sector, or an industry. It provides a common vocabulary, so officials from all levels of government can communicate easily with one another and to the public. It provides clear, easy to understand factors which help measure threat.
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Here's how it works. The advisory system is based on five threat conditions or five different alerts: low, guarded, elevated, high and severe. They're going to be represented by five colors: green, blue, yellow, orange and red ...

The Homeland Security Advisory System is now administered via the Department of Homeland Security. It has been in place now for roughly 4½ years since the system has been in place. As such, examination of the historical terror levels according to the advisory system should show a notable improvement via a shift away from "Elevated" and "High" towards the "Guarded" or even "Low" terror threat levels. In order to test this hypothesis, per data from the DHS website, I graphed out the terror levels over the past 1,650 days:

As you can see, we have never, not once, dropped below the "Elevated" yellow level of terror threat. We have only once made use of the "Severe" terror threat level, and that was back in August after the liquid terrorist plot was exposed. That said, if we are so much safer than we were five years ago, why are we still living with an "Elevated" terror threat, meaning that there is a "significant risk of terrorist attacks"?

Plenty of others are examining the question of American safety in a post-9/11 world elsewhere. However, if the Homeland Security Advisory System is any indicator, I'd say things are clearly worse.