As even Rothbard has pointed out, the claim that "participating in the political process is implicit consent" thoroughly undermines the anarcholibertarian position. 130M Americans just voted for President, and 170M Americans are registered to vote. Only one concession could be more devastating to the anarchist position that this idea that all of these people are implicit consenters to our current political institutions. That concession would be to agree that not emigrating from America is implicit consent to the American State.
Voting is in fact a form of self-defense, not voting is unilateral disarmament, and these "implicit consent" arguments are a form of surrender. For more, see Roderick Long's Dismantling Leviathan From Within at http://libertariannation.org/a/f24l3.html#6.