The Problem With 'Libertarian Populism' Is That It Isn't Populist Read more: http://www.businessinsider.com/libertarian-populism-not-populist-entitlements-spending-2013-7#ixzz2ahmTwiDp

He added that the safety net should be principally left to voluntary organizations and the states, with the federal government as a last resort. This approach has obvious public-finance problems (well, obvious to most people except libertarians): Demand for safety-net programs moves with the business cycle — inversely to tax receipts — so the ability to run a deficit is key to backing them, and the federal government is much better-positioned to do that than states are.

But a slash-the-federal-entitlement-state view also just isn't populist. Federal entitlements protect the masses against problems like unemployment, retirement insecurity, and poverty. Seeking to dismantle them is the opposite of defending mass interests against elites.
You can frame your desire to shrink these programs in terms of a desire to cut relatively regressive taxes like the payroll tax, as Carney does. But the progressivity that is lost by cutting entitlements is far greater than any that is gained by cutting regressive taxes.