Automatic defense cuts looming in January would be more devastating than previously feared and make it impossible for President Barack Obama to refocus his national security strategy, a bipartisan group of former lawmakers and retired military officers said Thursday.

Members of the Bipartisan Policy Center painted a dire picture for the nation's economy, the military and large and small defense contractors if the automatic reductions occur on Jan. 2, 2013. Based on a special task force's calculations, the group said the cuts would mean an indiscriminate, across-the-board 15 percent reduction in programs and activities within the military, not the 10 percent that had been estimated.

The gross domestic product also would be reduced by roughly half a percentage point, a blow to a struggling economy. About 1 million defense and nondefense jobs would be lost over two years, causing a spike in unemployment.

"An absolute fiasco," said former Sen. Pete Domenici, R-N.M., who served as chairman of the Senate Budget Committee.

Unless Obama, congressional Republicans and Democrats can agree on a plan to stave off the cuts, the military will face a reduction of $492 billion over a decade, with a $55 billion cut beginning in January, three months into the fiscal year. Domestic programs also would be reduced by $492 billion over a decade.

The automatic cuts, known as "sequestration," are the result of the failure last year of a bipartisan congressional panel to come up with a plan to cut the deficit by $1.2 trillion over 10 years. The panel had been created in the hard-fought budget law passed last summer that reduced government spending while raising the nation's borrowing authority.

Defense Secretary Leon Panetta unveiled a new military strategy earlier this year that reflected the drawdown of two wars in Iraq and Afghanistan and shifted the focus to future challenges in Asia, the Mideast and in cyberspace. The strategy also was driven by pressure to reduce the nation's deficit. The budget law that Obama and congressional Republicans backed last year called for reducing projected defense spending by $487 billion over 10 years.

Retired Marine Gen. James Jones, who headed the U.S. European Command, said if the Pentagon faces automatic cuts on top of the already planned reductions, "it makes the president's strategic guidance" impossible to execute.

Domenici, former Rep. Dan Glickman, D-Kan., Jones and the other retired military leaders implored Congress to act now to avert the cuts and not wait until after the election by producing broad legislation that deals with programs such as Medicare and Social Security as well as taxes. The report from the respected group is certain to add to the clamor for Congress to address the issue in the near term.

So far, however, proposed legislation from Republicans to prevent the defense cuts has targeted members of the federal workforce, a nonstarter for many in Congress, especially Democrats.

It's also unclear whether the Pentagon, unrivaled in its planning for any contingency, has a blueprint for how it will operate with across-the-board cuts.

Sen. John McCain of Arizona, the top Republican on the Armed Services Committee, is pushing an amendment to the nonrelated farm bill that would require Panetta to spell out the impact of the automatic cuts on national security by Aug. 15. The Senate is debating the farm bill this month.

McCain expressed frustration with the Pentagon for failing to outline a plan and wondered if the Pentagon is purposely avoiding a discussion of the ramifications, either because it doesn't believe sequestration will happen or because it doesn't want to show it could operate with fewer dollars.

"They don't want to describe the impact of it which then ripples down to the defense industries, the bases," McCain said in an interview. "With this kind of sequestration, you're talking about defense industries that are literally out of business."

Members of the task force told reporters at a briefing on the report that lawmakers face a largely unknown political peril. The 1989 Worker Adjustment and Retraining Notification Act requires employers to provide notice 60 days in advance of plant closings and mass layoffs. It applies to companies with 100 or more employees.

Sixty days prior to the Jan. 2 automatic cuts is Nov. 2 — four days before the November election.