I researched what caused the Federalists and Whigs to collapse. The Federalists stopped winning elections, faded into irrelevancy, and supported the adversary in a foreign war. That's what I hoped would happen to the Republicans. It's not happening, at least any time soon. The Whigs were riven by divisions over slavery and failed to renominate their own sitting President. That was the last straw and opened the door for the Republicans to take over their slot as a major party. The Democrats have just failed to renominate their own sitting President, although the details are different. It encourages me that the Democrats were on the wrong side of the Civil War and still survived, but that's cold comfort right now.