Actually, under U.S. law, they can't require you to have a license, but like everything else they do, they just do it and the masses allow it. Just ignore your rights long enough and they'll go away.
Many courts have ruled on this. I can't remember the exact wording of the law because it's been a while, but it says something to the effect that they can't regulate your travel using the "accepted means of the day." Requiring you to have a license means they are giving you permission, like it's a privilege, when travel using "accepted means of the day" is a right, not a privilege.
Of course, if you actually challenge it, most of the time you get a judge who doesn't care about the law (I've heard of one who actually said not to bring the constitution into his courtroom) or a lawyer who doesn't know it.
Same with income tax. Under the constitution (read it), it says that they can't tax your wages. They can tax business profits, but not the wages of your labor. If you bring up the 16th amendment, which supposedly gave them the power to do it, there's 2 problems with that:
(1) The Supreme Court has ruled that it actually did NOT give them the power to do it.
(2) The amendment itself was never actually ratified by enough states. It was "proclaimed" ratified by the secretary of state at the time, because they wanted it whether the people approved it or not.
A lot of laws on the books right now are totally illegal, but the people put up with it, so they keep doing it.
And to head the trolls off at the pass, "google it".