Dear Mr. Dfwgator,
I am sorry, but I have to disagree respectfully: it was by no means certain that the Nazis would have come to power.
Yes, they used deception to a degree unheard of in the 1200 year long history of the German people. If Hindenburg had been clear about Hitler‘s motives, he certainly would not have appointed the tyrant as Chancellor.
Or if Germany had been allowed to remain a constitutional monarchy.
Even if William II might have been forced to abdicate in favour of his son (or grandson, for that matter - there was the idea of making the grandson, young Prince William, the new Emperor, with Prince Max of Baden as Protector of the Realm during the former’s minority years), I cannot see either of them appointing Hitler as head of government.
However, I make no bones of the fact that, in the case of Germany, I would always have considered a constitutional monarchy the best solution. After all, this had been a time-honored tradition since the year 800 😀
Hitler's agenda and motives were clear to everyone from day one, he not only never tried to hide them, he spelled them out in most of his speeches and in Mein Kampf.
The reason Hindenburg and his circle were willing to appoint Hitler as Chancellor is that they believed that he - an Army Corporal and high school-dropout, would be stupid and easy to control by elite military officer and technocrats. In fact, he proved to be much more clever and politically astute than they gave him credit for, and Hitler wound up running circles around his "betters" like von Papen, von Schleicher, etc.
There was also some aspect of desperation to the appointment of Hitler - had the Communists and Socialist Democrats been given more time and had they formed a coalition, they would have had a Reichstag majority and created a government - in which case Hindenburg and Co. would be stuck with a Marxist as Chancellor, something they wanted to avoid at all costs. There's also the fact that Hindenburg was physically and mentally rather frail in his final years (he was in his mid or late 80s when he died, I believe), so his ability to control what happened after Hitlers appointment was limited.