What's a president to do? Jefferson and Louisiana

Thomas Jefferson had once been a Federalist, in the sense of supporting ratification of the Constitution of 1787. He had missed the convention that drafted the Constitution, being in Paris serving as America's minister to France. He would have suggested some modifications of the final version. But on the whole he considered it an improvement over the Articles of Confederation.

Even so, there was one clause that continued to worry him. In Article I, at the end of the enumeration of the powers granted to Congress, there was a catch-all phrase that seemed dubiously expansive, allowing Congress “to make all laws which shall be necessary and proper for carrying into execution the foregoing powers.” This would come to be called the elastic clause, in that it appeared able to stretch to accommodate the ambitions of officials intent on aggrandizing the federal government.

Jefferson didn't like it. He preferred limited government to expansive government, and he preferred the state governments to the federal government. He considered government a necessary evil, and he considered the federal government the least necessary and potentially most evil.

Such, at any rate, was his judgment when he was not running the government. He criticized Alexander Hamilton's program of federal assumption of state debts and creation of a national bank. He crafted a theory of state nullification of federal law following John Adams's signing of the Alien and Sedition Acts.

In no small part as a result of the furor caused by the Alien and Sedition Acts, Jefferson succeeded Adams as president in 1801. He hadn't been president long before his strict interpretation of the Constitution was put to a stern test.

Napoleon, emperor of France, surprisingly offered to sell the French territory of Louisiana to the United States. Jefferson recognized a good deal when he saw it. But his narrow reading of the Constitution failed to find authorization for the president or Congress to acquire new territory. And having criticized Hamilton's broad interpretation of the necessary-and-proper clause, Jefferson was loath to stretch that clause himself.

He pondered proposing an amendment to the Constitution. But he realized that amendments take time, and that his opponents would be tempted to drag the process out if only to watch him squirm. He knew that Napoleon was a mercurial sort who might change his mind and withdraw the offer if the Americans didn't accept it at once.

Torn between his philosophy of government and the needs of the moment, he opted for the latter. He accepted Napoleon's offer. In doing so he shattered his reputation for consistency, permitting his opponents to denounce his disregard of the Constitution in language much like he had deployed against them.

Yet even as they skewered him, Jefferson's opponents agreed with him that the Louisiana offer was an opportunity that mustn't be missed. The purchase went through, and the area of the United States nearly doubled. Jefferson's scruple-swallowing permitted another century of American expansion, across the western Mississippi Valley. No single action by any American president did more to ensure the emergence of the American economy as the envy of the world, and the United States as the global power enabled by that economy.

But the addition of Louisiana also set in motion dynamics that would tear the country apart. The secession crisis and the Civil War pitted North against South, but the sharpest dispute between those two regions was over the future of the West. Would it be slave or free?

The Louisiana Purchase has long been considered the greatest bargain in American history—500 million acres for $15 million. The Civil War cost the two sides $6 billion, not to mention several hundred thousand lives. Perhaps the Jefferson's bargain, though still a good one, was less than it seemed.