Further, while Woods is absolutely correct in saying that an unconstitutional Federal law does NOT constitute the "supreme law of the land" under the Supremacy Clause ("This Constitution,and the Laws of the United States WHICH SHALL BE NADE IN PURSUENCE THEREOF; and all treaties made, or which shall be made, under the authority of the United States, shall be the supreme law of the land; and the judges in every state shall be bound thereby, anything in the constitution or laws of any state to the contrary notwithstanding." [EMPHASIS added]) nullification would seem to contradict the intent of the Supremacy Clause by allowing the states to unilaterally nullify Federal law, perhaps for reasons of "faction" or for passing advantage.

Indeed, the reason for adopting the Constitution and forming a more powerful Federal government was to increase the utility of the Union, for example, by preventing states from obstructing the flow of commerce from other states or keeping the states from fighting border fights (neither of which was unknown under the Articles in the 1780s), while avoiding the usurpations of Liberty that the Colonists perceived during the 1760s and 1770s under Lord North's government.  To do this, a powerful and centralized, but not totalitarian, Federal Government was required.  Nullification seems to defeat this purpose.

However, the evidence is that nullification was not thought clearly unconstitutional by the Framers.

While it is not set out in the Constitution , neither is it prohibited. Possibly, the Framers believed that the House being elected by the People while the Senate was selected by state legislatures would preclude these issues or that the right to petition the government would resolve these issues. Neither did, but James Madison's support for the nullification of the Alien & Sedition Act by Virginia and Kentucky in 1798 provides evidence that nullification was NOT considered per se unconstitutional, certainly not as an act of protest.

However, as described above, it remained strikingly ineffective in my view as a practicing attorney. It seemed, in the immortal words of Rocket J. Squirrel, "Again?  That trick never works!"

Then I realized that the virtue of nullification lies not in directly changing law but in marshalling consensus and demonstrating resolve.  It does not, it cannot change the law by itself, but heralds the political will to change the law or the state of political power

While the Alien & Sedition Act might have continued to be enforced by US Attorneys in Federal Courts in Virginia and Kentucky in 1798 and 1799, by the election of 1800 the electorate had turned against John Adams and the Federalists.

While President Jackson might have forced South Carolina to back down in the Nullification Crisis of 1832, Congress quickly mitigated the "Tariff of Abominations."

While the Supreme Court forced Wisconsin to back off from its nullification of the Fugitive Slave Law, that act of nullification demonstrated that the states of the north were no longer content to live in  (per Lincoln's phrase) "a house divided."

Nullification, like jury nullification which has tacitly existed in American common  law since Zenger's case in 1733,, is not law but a check on law.  Since it is equitable but lawless, and always runs the risk of anarchy but tends to moot "lawless order," it must be a last resort.  

Louis XIV said that artillery was "The Last argument of Kings."  If so, Jury nullification is the last argument of juries and nullification is the last argument of state legislatures.