Of those, I had to vote for Hoover... the first President to oversee a recession that was still getting worse after three years, and didn't involve a war on US territory. There are substantial arguments that the extended duration of this recession was CAUSED BY his policies, and that the inflationary bubble that led to the recession was also CAUSED BY his policies as a senior official in the prior administration - and that at least the inflationary bubble and beginning of the recession he caused DELIBERATELY.But what of the guy who campaigned explicitly against those policies and pointed out how much harm they were doing, won election, and promptly expanded and enlarged them? "X is causing disaster - so let's do twice as much of it" - would that not be even worse? That is exactly what Franklin Roosevelt did.And the Civil War was, at the top level among the politicians, between: people who wanted to preserve slavery and were willing to destroy the Constitution to do so; and people who wanted to destroy the Constitution and were willing to either preserve or end slavery, whichever was more convenient, to do so. The latter won, and slavery was ended - and so was the primacy of the idea that the national government has only those powers the Constitution grants to it.