The assessment, done by the nation's top military officer, Gen. Peter Pace, chairman of the Joint Chiefs of Staff, represents a worsening from a year ago, when that risk was rated as moderate.
The report is classified, but on Monday senior defense officials, speaking on condition on anonymity, confirmed the decline in overall military readiness. And a report that accompanied Pace's review concluded that while the Pentagon is working to improve its warfighting abilities, it "may take several years to reduce risk to acceptable levels."
Pace's report comes as the U.S. is increasing its forces in Iraq to quell escalating violence in Baghdad. And top military officials have consistently acknowledged that the repeated and lengthy deployments are straining the Army, Marine Corps and reserve forces and taking a heavy toll on critical warfighting equipment.
The review grades the military's ability to meet the demands of the nation's military strategy — which would include fighting the wars as well as being able to respond to any potential outbreaks in places such as North Korea, Iran, Lebanon, Cuba or China.
The latest review by Pace covers the military's status during 2006, but the readiness level has seesawed back and forth during the Iraq war. Officials, speaking on condition of anonymity because the risk levels are classified, said the risk for 2005 was moderate, but it was assessed as significant in 2004.
His assessment was submitted to Defense Secretary Robert Gates at the beginning of this year, and therefore does not reflect the latest move to pour 21,500 more troops into Iraq over the next few months.
Gates delivered Pace's assessment to Congress, along with a six-page report on steps the Pentagon is taking to address the problem —including new efforts to increase the size of the Army and Marine Corps, and requests for more money to repair and replace equipment. On Monday, the Pentagon released most of Gates' report, except for a few sections that were classified as secret.
That report concluded that "world events and regional trends add up to increased challenges to our nation's security." And it said the decline in readiness is also affected by whether other federal agencies and other nations are fulfilling their commitments.
There have been long-standing complaints that the State Department has not met its responsibilities in Iraq, particularly in reconstruction and rebuilding efforts, as well as buttressing the political development of the Iraqi government.
In his report, Gates also discussed efforts to repair and replace equipment worn out in combat, beef up recruiting and retention, and make better use of the National Guard and reserve forces. It also details how the Pentagon will use billions of dollars in the proposed budget, including plans to modernize aircraft and weapons, develop better detection and countermeasures for weapons of mass destruction, increase the size of the special operations forces, and boost the nation's missile defense.