During and after the Civil War, Republicans worked to bring in sparsely populated states such as Idaho, Nevada and Wyoming to help the party retain power. So from 1875 to 1897, the GOP controlled the Senate — which was elected by state legislatures back then — for nine out of 11 Congresses even though Democrats held the popularly-elected House eight times. As a result, Democrats achieved unified control of government (including the presidency) for just one of those 11 Congresses. This helped the GOP protect many policies it had put in place as the dominant party during the Civil War and Reconstruction. Plus, Republicans controlled both the presidency and Senate for more than half that time, enabling them to make favorable judicial appointments that helped preserve the party’s preferred laws.

With this history in mind, Democrats could take statehood politics to its logical extreme. Democratic Sen. Brian Schatz of Hawaii recently tweeted that American Samoa and Guam should get voting representation in Congress along with D.C. and Puerto Rico. Statehood for Guam might seem outlandish — as of the 2010 census, it had about 160,000 people, much less than even the least-populous current state, Wyoming, which was home to 560,000 people. But some states the GOP brought into the union during the late 19th century had far fewer people than the average House district. Nevada was particularly egregious — it became a state in 1864 but had an estimated population of only about 21,000 people, 17 percent of the average House district at the time, according to research by Stewart and his co-author Barry Weingast of Stanford University. As of 2010, the average House district had about 710,000 people, so Guam’s population would be equivalent to about 22 percent of the average district, comparably larger than Nevada’s in 1864. If Democrats could get full control, were willing to sacrifice the filibuster and really wanted to go all out, pursuing statehood for all U.S. territories might be an end that would justify the incredibly incendiary means.