Terrorism is said by some to be the greatest existential threat since the Soviet Union, but a new study claims that if you discount Iraq, the number of people dying in terror attacks fell last year.

Here's CTV.ca video of a Canada AM interview with Simon Fraser University's Andrew Mack.

Here's the BBC story by its security correspondent Gordon Carrera:

Three weeks ago, the US released its "Country Reports on Terrorism" for 2007, described as a reference tool for the war on terror.

It highlighted the many plots disrupted over the year around the world, warning that al Qaeda leaders had "reconstituted", and "continued to plot attacks".

But today, a different view comes from the Human Security Brief for 2007 which comes with the contrasting headline: "Terrorism Fatalities Decline as Muslim Support for al Qaeda Terror Network Plummets."

"The expert consensus is over-pessimistic," argues the report's author Andrew Mack.

So what is the real picture?

Unfortunately, the answer is that much of it comes down to how you measure and think about the terrorist threat.

Mack suggests that fatalities from terrorism declined 40 per cent in 2007, when one eliminates Iraq (his study makes the suggestion that Iraq is mostly in the throes of a civil war).

Carrera makes the point that declining numbers don't mean a declining threat.

Al Qaeda isn't in the numbers game. Its two main principles for planning attacks are that it be more spectacular than the last, and most importantly, that it not fail.

I hold to the belief that if al Qaeda could pull off a nuclear attack (most likely a dirty bomb) in the core of a major Western city, it would do so.

Laziness, incompetence and a "failure of imagination" led to 9/11. A lack of vigilance could lead to another mega-attack in which thousands could die.

However, the report also states that support for al Qaeda is plummeting in the Muslim world, especially Pakistan. However ...

This, though, is partly a reaction to the violence that has moved from the tribal areas of Pakistan into the heart of the country.

Diminishing appeal

The reaction may signal declining support for Bin Laden amongst the general population, but it is a product of a much more real terrorist threat.

In a sense this reveals one of the complex problems involved in trying to measure whether terrorism is growing or not.

At exactly the time that terrorism may be a more real threat for people, support for it is likely to decline. ...

There are certainly signs that al-Qaeda's appeal is diminishing to the wider community of Muslims.

Bin Laden's audio and video messages create relatively little chatter on the web forums in the way they used to.

In the long run this trend is bound to reduce the terrorist threat but it may take some time, and the concern is that there are already large numbers of individuals who have already been radicalised, and are still determined to commit acts of violence.

A single major attack like 9/11 could transform the statistics.

The news coverage has focused on the terror angle, but there are other aspects to human security. There are still some nasty civil conflicts raging in Africa (Congo, Darfur), but the report claims that the situation is also improving in sub-Saharan Africa:

Between 2002 and 2006, the number of "one-sided campaigns" of violence against civilians fell by two-thirds, and their death toll by more than 80 per cent.

Part of this is due to success in reducing poverty, the report said, noting that wealthier countries are more stable. But the other part is the world's post-Cold War emphasis on peacemaking and post-conflict resolution (much more could be done on conflict prevention).