WASHINGTON — A marked decline in the number of explosive devices coming into Iraq from neighboring Iran has helped reduce the frequency of deadly attacks against U.S. service members, a top U.S. general said Thursday.
The military's view reflects a growing belief that Iran has reduced its level of interference in Iraq and is no longer, as the U.S. alleges, providing weapons that are used to kill U.S. troops, potentially making it easier for the next administration to reach out to the government in Tehran.
President-elect Barack Obama said during this year's political campaign that he was willing to meet with Iranian leaders, a stance criticized by conservatives who cited Tehran's support of violent anti-U.S. Shiite militias.
Now, however, there has been a steep reduction in the use of armor-piercing bombs, also known as explosively formed penetrators, particularly lethal weapons that U.S. officials say often are designed or built in Iran.
There once were as many as 80 such attacks per month, but the number now is as few as 12, Army Lt. Gen. Thomas F. Metz said at a meeting with reporters.
Metz is director of a military organization whose aim is to reduce the effects of roadside bombs on U.S. troops.
"In the past three months, they have gone way down," Metz said. "Someone has made a decision on the Shia side in connection with Iran . . . to bring them down."
Armor-piercing bombs now being found are less-sophisticated versions built in Iraq, not smuggled in from Iran, he said.
The devices never accounted for more than about 5% of all roadside bombs but have caused about 35% of the casualties, Metz said.
The sophisticated bombs work by turning a copper plate into a shaped projectile. The molten copper, formed by the bomb's explosion, can penetrate most armor on Humvees and other U.S. vehicles. The slug turns the vehicle's armor into shrapnel that blasts through the vehicle.
The U.S. has long accused the Quds Force of Iran's Revolutionary Guard Corps of supplying armor-piercing bombs to Shiite militias. But Metz said that, based on the data he had seen, the Revolutionary Guard has pulled back the number of weapons being smuggled into Iraq.
"I am not in the intelligence business, but that is the conclusion I would draw," Metz said.
Metz's comments were echoed by Ali Dabbagh, the Iraqi government spokesman, who said Iran had taken a more "positive stance" in recent months. Dabbagh said a new security agreement between Baghdad and Washington has helped ease Iranian fears about American intentions.
"The Iranians have noticed finally that the American . . . presence in Iraq is not going to be a threat to them and that helps reduce the temperature," he said.
But Dabbagh said a deeper dialogue with Tehran is needed and that Iran must do more to respect its border with Iraq.
"Iran should understand: To be a good partner they should respect international law and refrain from interfering not only in Iraq, but the region," he said.
At the height of the Iraq war, between October 2006 and June 2007, the military saw as many as 2,500 improvised explosive devices on the roads of Iraq per month. That had fallen to 415 in November. Only 29 of those bombings resulted in U.S.-led coalition deaths or injuries, according to the Joint Improvised Explosive Device Defeat Organization, the effort that Metz leads.
The U.S. military's death toll from roadside bombs was two each in October and November, the lowest since the beginning of the war, according to the organization.
Although the number of roadside bomb attacks has declined in Iraq, they have risen in Afghanistan. Last month they reached 315, compared with 274 the previous November and 96 in November 2006.
Metz credited an overall decline in violence in Iraq to new strategies devised by top generals in Baghdad. But he said his organization also helped soldiers and Marines in Iraq do a better job at rooting out bomb networks.