Always makes me sad when people forget that AC's are not the same as WoW's talent trees, skilltrees are for that. AC's = pretty much the same as a class in any other MMO. It's not like you can change your class in WoW now, is it? If you want to tank, pick an AC that can tank like someone already said. You can always respec to for example Firebug if you wish to dps as a Powertech or something.