As Micah Zenko points out, between 2000 and 2010 an average of 29 US citizens were killed each year by falling televisions, dressers, and other household furnishings. Yet we haven't declared war on the killer flat-screens rampaging through the heartland.
To be sure, terrorism is declining from a high base, thanks to the surging use of the tactic in Afghanistan and Iraq following the 2002 and 2003 US-led invasions of the two countries. Last year, the US military presence in Iraq was mostly about packing up and leaving, with far fewer patrols or offensives. Iraq, still the second most terrorism plagued country in the world by the US reckoning, saw attacks fall sharply last year. There were 13,600 people killed in terrorist attacks in Iraq in 2007, and that number fell to 3,654 by 2009 and to 3,063 last year.
And then there are issues with how "terrorism" is defined.