I don't think "own" means what you think it means :-). If there were no government, you would "own" something until someone with a bigger club comes around. If there is a government obeying the rule of law, you "own" something until your ownership is removed by due legal process. Expropriation is limited in scope and requires renumeration (U.S.C. 5th amendment: "Nor shall private property be taken for public use, without just compensation."), so ownership is more than a temporary lease, but it is certainly no unlimited perpetual right. Hint: there's not an awful lot of those :).
In Dutch law, ownership is defined as the maximal rights that one can enjoy on a good. Not "full" or "unrestricted" rights, but "maximal".
(and yes, if you start breaking the law, either by refusing to pay taxes or in some other way, you will find that a lot of your rights are quite relative, including ownership, freedom of movement and ultimately freedom from physical abuse)