Would you be? The British and French were right to dismantle them- the german states were nothing but trouble in europe, constantly taking advantage of every slight instance of instability to tear it apart. While some may argue it filled a vaccum in Europe's balance, it did more harm than good.
And what they did to their "lesser peoples," is sickening to all good people. Again, some may argue the british were no better, those people forget what Britain did was only to dissenters and criminals. Not ideal, but not genocide. If it wasn't different, American aid wouldn't have helped rebuild the empire to prevent radicalization in the would be decolonized nations. Same with France.
I would not be nice to Germany. If anything, much of Germany got off a bit too easily.
Chopping up Germany, the blame ultimately got pinned on the "Prusso-Saxons" and Austria, Bavaria, and Rhineland were portrayed as states "freed from Junker domination" which is a peculiar narrative given the NSDAP's origins in Bavaria and Hitler's own Austria. The ardent anti-Nazis and pro-western liberals Konrad Adenaur, Ludwig Erhard, and Otto von Hapsburg being the respective faces of post-German Rhineland, Bavaroswabia, and the United States of Greater Austria (Austria, Hungary, Slovakia, and Zakarpattia) helped sell a narrative that these regions were anti-Nazi and dominated by the Prusso-Saxons, but it also helped these countries escape responsibility for their role in the actions of the Reich and the Axis.
Plus, the need to disproportionately milk Saxony for reparations money limited how much land could be given to Poland. Instead of a border on the Oder and Neisse, the border is along the Oder. There were proposals for Stettin and Silesia south of the Oder to be Polish, but those were nixed so that Saxony could be economically productive enough to pay reparations. Odds are, the western boundary of Saxony would be on the Elbe rather than the Weser for similar reasons if so much of the money didn't need to come from Saxony.
The French certainly made good use of the Palatine and Saarland Germans. They stuck them all in Algeria. That was certainly one way to boost the number of people loyal to France...
Morgenthau's biggest mistake was accepting the idea of "to keep Germany down, we must bolster France". He looked the other way as the French seized Aosta, Imperia, Elba, and the eastern slopes of the alps - resulting in Italy going red. It wasn't until the French seized Wallonia during the Royal Crisis induced Belgian Civil war that the US realized that Paris was intent on returning to its old aggressive ways.
With regard to Britain, America pushed decolonization hard in most of the Empire. The areas where the US propped up the British were Malaya, Borneo, the Indian Ocean possessions, Cyprus, Malta, South Arabia, the Gulf Protectorates, Zanzibar, and Hong Kong. The US forced the British out of Africa real quick. The possessions the UK retained were all ones that
desired continued British protection which is a pretty big distinction from "the US propped up the British Empire". The one big exception is probably the continued protectorate of Ceylon. But compared to getting out of India and Africa, that's somewhat small. All of these places either wanted to remain British or had very significant strategic implications.
Although, the US perhaps could have pushed harder against the divvying up India into Pakistan, Bharat, Kashmir, and Bengal.