Since then, the Federal Goverment has encroached upon not only the states, (14th Amendment; 17th Amendment), but even local government (Civil Rights Acts is the prime example of this). A few specific dangers provided by the Anti-federalists include: 1) No check on federal judicial power; 2) No check on the power of the Federal Government due to the "welfare" clause; 3) Complete and unquestionable (by the states) taxing authority given to the Federal Government.
Many believe that the Constitutional Debate was about states rights, but that's not true. Some delegates argued for elimination of the states altogether. Keep in mind the Federalists won one of America's first PR battles by seizing the title of "Federalist" for themselves and leaving the opposition with "Anti-federalist". At the time the word "confederacy" and "federation" meant exactly the same thing. The Federalists were actually Nationalists and the Anti-federalists were the true Federalists. Whatever party or movement comes out of all this present day crisis, if we are ever given another chance at freedom and self-government, we must address the issues pointed out by the Anti-federalists.