and introduced some kind of control over the growing corporations so that socialism would never have gotten a foothold
I'll never understand this thinking, that to dismiss something undesirable we must adopt part of it. We mustn't speak the language of what we do not want. The so-called "corporate" system gave jobs, organized capital, created goods, solved problems, and empowered a people to build the greatest civilization in history. Abuse? Yes, only in violation of traditional American standards. Poor people and living conditions? Yes, and in violation of American ways, and not because of them. We must speak of America unto herself, and not by some other definitions. To consider capitalism's excesses as responsible for socialism is to assume the tenets of socialism.
To what standard would you have President Grant hold the system: min. wages? hiring/firing rules? retirement programs? public ownership? Socialism wants nanny care, redistribution of wealth, and state control. American principles, on the other hand, demand honesty, fairness, fulfillment of contract, and good neighborliness. Whatever Grant might have done to promote these principles is in no way related to the advent of socialism. I agree with you that Grant missed the opportunity to hold corporatism to the higher standard. But that is entirely unrelated to socialism.
Socialism finds any convenient excuse, and it has held the corporate system as a straw man. The abuses of capitalism cannot be blamed for fomenting socialism. If we accept that then we are not holding socialism to account for itself. Eric Rauchway wrote a book all about this idea that we must adopt socialism in order to kill it: Murdering McKinley : The Making of Theodore Roosevelt's America (Amazon link).
[Btw, I use the word "capitalism" for convenience only. It is our politics that defines our economics, not the other way around.]
Thanks for reading my mind. I need say no more.