Please. Anarchists (esp. anarcho-capitalists) have made up a significant portion of libertarians in the US since the Vietnam war. The 1974 Libertarian National Convention intentionally made the Libertarian Party platform ambiguous on the desirability of the state's existence (the Dallas Accord) in order to stave off a full scale war between anarchists and minarchists for goodness sakes.
Plenty of libertarians would be happy to abolish government altogether and truly believe that we'd all be better off for it.
And how do you suppose rights are to be enforced if not the constituted government? By saying please? Or everybody shooting it out? Hope you're a good shot or your 'rights' go out the window.
And, how do you square an appeal to the framers of the Constitution for limited government with the actual decisions of those framers over the first 30 years of the US Government?
In establishing a process that allows for the orderly application of the input of the governed, of "clearing the channels" for democracy, the Constitution has been an extraordinarily effective instrument. In establishing the fundamental principles and values of that government --- something it barely even tries to do --- it is much less effective. Searching the Constitution for principles and values inevitably involves an element of tea leaf reading; pretty quickly you're out of the text of the Constitution and into the Federalist Papers, and now we're talking about a rule by three dead guys.
Note that the U.S. Constitutional scheme is not one of minarchist government. The powers of the federal government are limited to those enumerated, but the scheme presupposes the existence of state governments, whose powers are nearly unlimited.[1] Moreover, the Constitution guarantees that these state governments will have republican form.
[1] More or less, the states were considered to have inherited the sovereign powers of the British Parliament, which were limited only by unwritten British constitution (i.e. the historical rights of Englishmen).
Libertarianism recognizes the value of governance, don't get confused, but it asserts that certain individual rights as inalienable.