AHC: Sideline The US Senate Before 1900

whether passed by Congress or a convention, there still has to be ratification by three-fourths of the states, and some of those three-fourths will definitely be among the small states that get disproportionate power through the Senate.
And furthermore, any amendment which leaves any state with less representation than any other state has to be approved by that state. For instance, an amendment adding a Senate seat for the five largest state would have to be approved by all 45 other states.

An amendment transferring powers from the Senate to the House or to some other body would not change the equal representation in the Senate, but would break equal authority in the affected powers - which arguably has the same effect.
 
The US Senate is as far as I can tell the ONLY example of the less democratic house having greater power on the planet at the moment and probably into the 20th Century
 
Have the feeling arise during the Civil War that this is what State's Rights get you, and a movement to weaken those aspects of the Constitution that embody that.
 
Perhaps the fight over slavery boils over into civil war earlier, with the result of there being fewer small states to object to the new order, and for the North to have a less overwhelming industrial advantage to cause the war itself to last even longer, perhaps with the South making significant inroads into Northern territory and possibly even burning D.C., before the North finally mobilises proper and crushes them, and committing totally to Reconstruction, weakening the Senate to neuter the lower-population Southern states.
 
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