Crooks & Liars sums it up best (link here):
"The math is wrong and so is their attitude
Social Security’s attackers claim that they’re concerned about the program’s financial future. But their math doesn’t add up, and their hostility isn’t really about dollars and cents. Instead, it’s about ideology and posturing. And underneath it all is ignorance of or indifference to the realities of life for many Americans.
So where do claims of crisis come from? To a large extent they rely on bad-faith accounting. In particular, they rely on an exercise in three-card monte in which the surpluses Social Security has been running for a quarter-century don’t count — because hey, the program doesn’t have any independent existence; it’s just part of the general federal budget — while future Social Security deficits are unacceptable — because hey, the program has to stand on its own.
What's really going on here?
What’s really going on here? Conservatives hate Social Security for ideological reasons: its success undermines their claim that government is always the problem, never the solution. But they receive crucial support from Washington insiders, for whom a declared willingness to cut Social Security has long served as a badge of fiscal seriousness, never mind the arithmetic.
There's much more to Krugman's article, all worthy of attention. Bottom line is easy: Social Security should not be on the table", doesn't need to be on the table, and has no business on the table of rational, fact based, realistic Americans. At all.