Theft it the taking of another person's property without that person's permission or consent. Taxation, to many Americans, is done involuntarily. In this process, the government forcibly extorts money from its citizens in order to finance its expenditures.
Many would argue the ends justify the means and that as long as tax money goes to the important functions of government that the people want, then taxation is warranted. The problem with this argument is that not everybody wants the government to provide certain services; some would rather pay a private business or entity to do so. If Person A did not want an apple and Person B decided to put one the hand of Person A and take a dollar from his pocket, are Person B's actions justified? No. How is taxation any different?



