It "seems pretty clear," is the problem. If liberty is defined as being free to do whatever one chooses without interfering with anyone else's liberty, what you suggest is impossible. In fact, thus defined, every other relationship between individual means that someone is usurping authority over another individual's life. The correct name for that is tyranny.
Those are your choices, liberty or tyranny. Most people are petrified of liberty, because it also means they must be responsible for their own lives. Most people prefer tyranny.
Hank
That comes pretty close to my definition of libertarianism. I believe it is also not too far from "classical liberalism." I believe it is also not far off from what our founding fathers had in mind.
"Absolute and unrestricted liberty" is not what I think of as libertarianism, but was suggested by another poster. However alot of folks who call themselves "Libertarians," such as the ones at Lewrockwell.com, seem like damn fools.