I can't really see Hobbes as the founder of conservatism. There were conservatives of a sort before he came along -- supporters of local and national traditions. Hobbes was pretty unreliable in that regard, a supporter of powerful government in a way that most conservatives today would be uncomfortable with.
Applying "liberal" and "conservative" to anything before the French Revolution is pointless. Who was the true conservative, a king who represented the nation and stability but forever increased his own power, or a nobleman who fought centralized monarchical power to the point of elevating his own whims over everything else? It's hard to say.
I'd always heard Lyndon Johnson first "raided" Social Security. Actually what he did was to count Social Security receipts as government income to make it appear that the budget was already balanced, when he was actually running a deficit.
Some people say Reagan, followed by Bush and Clinton, first borrowed from Social Security. Others say that the program was always pay as you go and the "trust fund" or "lock-box" was a myth, so the answer would actually be Franklin Roosevelt.
If you want an answer try "answers.com." They have five different ones. One of those must be right.
Very good point about how the meaning of terms change so much over time as the context changes, so really, how relevant is to talk about conservatism and liberalism of 200 years ago? I think it’s mostly relevant in terms of the basic view of human nature and maybe in a general sense what constitutes a civil society. Thank you so much for your input - it’s very helpful!