It was held together by decorum. There is none left.
It seems to be a pattern, where a disturbingly-large minority of people remember nothing but the year-number of an election (e.g. "2008") and never account for how voting was at the end of that year and the voting-result only takes effect the next (odd-numbered) year.
Oh, there's also a general "I want it to be true so I remember it that way" aspect, but I think that's contributory rather than the main cause.
I recommend the surplus/deficit by GDP graph, which is easier than manually eyeballing slopes: https://fred.stlouisfed.org/series/FYFSGDA188S
1942-1945: Big increase to pay for fighting/winning a World War
1946-2007: More or less fiscally responsible
2008-present: War-like level of debt increase to counteract a down business cycle?