There is no comparison between Santorum and Romney.
Santorum is right when he says that conservatism is not libertarianism. Conservatism historically has accepted a low level of government involvement in both social and economic affairs. For example, it is right, in my view, for the government to support natural marriage with thru such things as spousal sharing of social security benefits.
That supports the rearing of children and the sharing of that load by both mother and father.
“Conservatism historically has accepted a low level of government involvement in both social and economic affairs.”
Exactly why neither is a conservative, thanks for pointing that out.