Introduction of the Income Tax
There was no federal income tax when Cordell Hull entered Congress, it having been struck down by the Supreme Court as unconstitutional in the Pollock case of 1895. Cordell introduced a bill for federal income taxes on December 19, 1907. The income tax had first been imposed during the Civil War, and had been advocated by the Farmers Alliance and others as a good way to finance the federal government. It had been included in the Wilson Tariff Act of 1894, before being struck down. Most pundits thought it would be impossible to pass a constitutional federal income tax.
At first Representative Hull made no progress getting Congress to even consider the tax, although changes in Supreme Court justices gave him hope that an enacted income tax would be okayed by the Supreme Court. He persisted, showing how many other nations used an income tax. Congress was ruled then by Speaker Joseph "Uncle Jo" Cannon, a Republican. Hull had to beg Cannon to allow the passage of a bill to build a new federal court in Hull's district. In 1908 election Hull's office was contested, but he won a second term.
In March 1909 Cannon was toppled from power by an alliance of Democrats with progressive Republicans. The main fight in Congress was over a new tariff bill, with convervatives favoring higher tariffs. Progressive Republicans favored lowering the tariffs, but raising revenue by initiating Hull's income tax. In the House version of the Payne Tariff bill the income tax was defeated, but Hull convinced Senator Joseph Bailey to add it to the Senate bill. To kill the income tax conservatives proposed a constitutional amendment to approve it. The removed it from the tariff bill, and thought it would never be ratified by the states. But enough states ratified it, so it became the Sixteenth Amendment, and thus could no longer be struck down by the Supreme Court. [p. 48-60]
Cordell Hull basically claimed credit for the modern income tax. He saw the income tax as the only way of raising large amounts of money for wars. The new income tax was in place just in time for World War I. 
In the 1910 election the Democrats won a majority in the House of Representatives, mainly because of popular opposition to high tariffs. They took away the power to make committee appointments from the Speaker and gave it to the Ways and Means committee. Hull was appointed a member of this committee. At the age of 39, he had become one of the more powerful members of the Democratic Party in the House. [62-64]
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