To help heal the nation’s economic sores, Washington could free up billions annually by drastically altering how it uses the U.S. military and shaving the size of the Army and Marine Corps, according to a new study.

As the White House and congressional leaders race to find a way to address the nation’s mounting debt, members of both political parties have said defense cuts are on the table. Even House Republicans, typically hawkish on Pentagon spending, say defense cuts are needed.

{mosads}“America’s current economic troubles require us, as a matter of long-term national security, to re-examine our policy choices in every area and ensure that they are wise, necessary and cost-effective,” states a new Institute for Policy Studies (IPS) report. “We must return to an emphasis on more traditional and reliable crisis response, defense, deterrence and conflict-resolution tasks.”

Such a shift in strategy “would allow a significant reduction in both the size and activity level of our armed forces, the study states. “Their activity would become more focused and their goals more discrete, determinate and realistic.”

While saying defense cuts should be made, no lawmaker — Democrat or Republican — has yet put forth a plan detailing where the Pentagon budget could be slashed and proposing where those cuts could come from as part of recent budget and debt deliberations.

Rep. Barney Frank (D-Mass.) has called for $1 trillion in Pentagon funding reductions over 10 years.

Notably, the fiscal-minded House freshman Republican class continues to be open to defense cuts, breaking with the GOP’s mindset of the past decade.

The IPS study — led by former Pentagon official Lawrence Korb and national security scholar Miriam Pemberton — offers a few ideas.

They propose shrinking the size of the U.S. ground forces — the Army and Marines — by 20 percent. The former currently has around 1.4 million active-duty and 850,000 Guard and Reserve troops; the Marine Corps has just over 200,000 active and 40,000 Reserve personnel.

Such a reduction would “yield a steady-state savings of $20 billion per year,” the study concluded.

While many in Congress want to find a way to build even more than the Navy’s stated goal of 313 ships, Korb and Pemberton recommend shrinking the sea service’s surface fleet by 20 percent, “including two [aircraft] carriers, and carrier air wings,” a move they say would save $10 billion per year over a decade.

The Air Force would lose two combat air wings under the IPS plan, for a savings of about $3 billion annually.

Whether hardware programs and force structure will be pared back in a likely round of defense cuts remains unclear.

{mosads}In a statement released Friday just minutes after he was sworn in, Defense Secretary Leon Panetta acknowledged the Defense Department will be forced to make “tough budget choices.” But he called it a “false choice” that fiscal discipline means weakening national security.

“Even as the United States addresses fiscal challenges at home, there will be no hollow force on my watch,” Panetta said. “That will require us all to be disciplined in how we manage taxpayer resources.”

Ending counterinsurgency-based military campaigns like those in Iraq and Afghanistan also would bring big savings, the researchers found.

“The recent cost of protracted U.S. counterinsurgency campaigns approximates $1 million per year for every deployed person,” according to the study.

President Obama recently placed the price tag for the Iraq and Afghanistan wars at over $1 trillion. But a Brown University study released Thursday put the actual price at $4 trillion.

“Conservatively estimated, the war bills already paid and obligated to be paid are $3.2 trillion in constant dollars,” the Brown study found. “A more reasonable estimate puts the number at nearly $4 trillion.”

The “human and economic costs,” however, will stretch for decades, with “some costs not peaking until mid-century,” the Brown report concludes.