Yglesias thinks it makes sense to cut money from Medicare rather than slashing Social Security:
What’s more, if we’re going to cut spending on retirement programs then such cuts should be broadly shared and not exclusively inflicted on younger people. Such moves are both fairer and more credible. Last, if you want to cut Social Security benefits you should just cut Social Security benefits.
But the retirement age has in no way caught up with life expectancy in America. I agree that Medicare is the more urgent target. I just don't see why we can't cut Medicare and raise the retirement age, as well as reduce the more utopian elements of the Bush-Cheney extension of empire in Iraq and Afghanistan.