I am by no means an expert on the subject on politics in the 1880s—though if I had time and the means I would certainly do research in the subject. I actually have great respect for Twain and other Mugwumps of the era, such as Nast. I think they had the best of intentions. However, in the end they ended up exiling themselves rather than having the influence and impact they so desired to have. I see a similar trend in politics today at both ends of the political spectrum. Of course, I rejoice in the idea that many on the left are engaging in their own brand of Mugwumpery, while at the same time I see this attitude as being counterproductive on the right.
It’s still a cool-sounding handle, though.