What the Tea Party wants is a smaller government they just think its too big and bloated right now. They just think its a good idea to go back to the constitution because the government would run better that way in their opinion and that's the way the framers intended the government to run in the first place.
What's wrong though is they want all the benefits of a big government (Medicare, Medicaid, Social Security and Department of Defense) without having to pay for it. They also don't seem to understand economics, how the government works, what the ACA does, or even basic arithmetic.
I don't think they find the 21st Century offensive its just different for them they are agonized that the government is 17-18 trillion dollars in debt.
They didn't object to the expensive wars and massive tax cuts.