(CBS News) WASHINGTON - The military retirement system has long been considered untouchable - along with Social Security and Medicare. But in these days of soaring deficits, it seems everything is a potential target for budget cutters. A Pentagon-sponsored study says military pensions are no longer untouchable - they're unaffordable. CBS News investigative correspondent Sharyl Attkisson reports high-level, closely-held meetings are taking place at the Pentagon regarding a radical proposal to overhaul retirement for the nation's 1.4 million service members - a bedrock guarantee of military service. The proposal comes from an influential panel of military advisors called the Defense Business Board. Their plan, laid out in a 24-page presentation "Modernizing the Military Retirement System," would eliminate the familiar system under which anyone who serves 20 years is eligible for retirement at half their salary. Instead, they'd get a 401k-style plan with government contributions. They'd have to wait until normal retirement age. It would save $250 billion dollars over 20 years. Radical overhaul of military retirement eyed - CBS News They talked about this during the Bush years. That's when they added the Thrift Savings Plan for the active duty military.