Best way to do this would probably to just get big business into government and have it refuse to make any concessions to anyone.
Blaine becomes President instead of Grover Cleveland; he is deeply in the pocket of major corporations. Big Business has simple ideas for what they want: No Unions, no wasteful taxes on helping the less fortunately, no government aid for disasters, High Tariffs and nearly total isolation from the world at large.
Government takes a turn away from popular rule towards oligophy. Hired Guns, like the Pinkertons, simply have open license to gun down strikers in the streets. This arrangement is unstable, and so corporations simply co-operate to ensure that they will hang together, or they will surely hang apart.
There's no reason to ensure that people hurt on the job get any kind of medical care. Screw them. No reason that factories can't hire "jolly elves" to work in their factories--can't their parent's have more children?
After Blaine, people like Roscoe Conkling and perhaps even CEOs themselves can take up the mantle. President J.P. Morgan, President Henry Ford. Each one more of the same, as democracy dies to the face of endless money and control.
The Proletariat would be impoverished, hungry, and left entirely powerless. The US Chamber of Commerce, the true nexus of American Power for well over a century, cares nothing for human rights abuses or environmental destruction. Why worry that Baltimore or Detroit is an unlivable hell-hole? Most of the important people of the United States live far away from those places where those simian workers live, therefore its cheaper not to care.
The idea of even providing basic aid to the needy falls to equally hard hearted religious institutions, which stress the Gospel of Wealth as a founding credo. Giving people access to basic medicine and sanitation would probably increase their lifespans and quality of life, but that would cost precious tax dollars that would reduce profits.
Banning Child Labor, Abortion and Infanticide, and proposing basic education for men (not for women) is beyond the scope of this one party system. The idea that the less fortunate might actually need help as opposed to conveniently dying and being replaced by someone cheaper is taboo in Washington, itself free of the intense smog, acid rain and trash that wreck much of the country. Social Security? This USA has privatized the post office...
Basically , this is an Industrial Age variant of Serfdom , with a so called "Capitalist" Aristocracy. I wouldn't even call it Laissez Faire - a Big Business Government of this fashion would probably strongly resemble the Command Economy of the USSR eventually in many ways , where a coalition of senior Capitalist Oligarchs cum Appartchniks dictate every form of production and business transactions , where monopolies dominate every single market .
The proletrait , highly uneducated , highly malnourished , and highly unmotivated would also be far more unproductive . Why bother working your ass off or giving your all if there's no prospect of social advancement or betterment ? Why Educate the proles ? Keep them in ignorance , doing menial tasks .
But eventually , such an economy would be highly unproductive . Indeed , I suspect we'll see a USA suffering 70's and 80's USSR Style social , and also some economic problems . Firstly , alcoholism and drug abuse rates would be through the roof. Crime would be extremely rife. Life Expectancy would be low . Productivity about as much as you might expect from a society virtually based on Slavery by another name. An uneducated population would also mean a extremely uncreative population . There will eventually be huge shortages of the necessary skilled workers needed to run an advance industrial economy, unless the US Oligarchy decides to implement a Federal Education Policy and system - in which case we would have a nascent social welfare state of a sorts. R&D would be rather low in the absence of competition.
Economically , the proliferation of Monopolies , though profit oriented might very well result from very similar inefficiencies that plagued the Command Economy. What's the difference anyway ? A Big Business state economy would likely be a Command Economy all but in name . If Big Business is the government , and an economy where the government dictates production , prices and allocation is a command economy , a Big Business government would essentially be a command economy, albeit one more intent on driving up prices to enrich the elites.
The question is how long this stasis can last ? All it takes are a few sufficiently large nations to realize that , at the very least , the provision of more equal opportunities would give them a significant competitive advantage to break this equilibrium, be it either by forcing every other county to follow suit , or in producing a war that wipes out civilization, Even the introduction of Roman style bread and circuses to keep the population down would be social welfare of a sort , mind you.
In the end though , this thread needs a definition of "Social Security " . The most extreme interpretation , where the government is completely controlled by business and run solely for the benefit of a Bourgeois - Aristocracy basically means we have one Huge Sovietized USA , without any of the pretense of being for the "masses" . This is very much a Vlad Tepes.
P.S By the way , I do think the Pinkertons would eventually evolve into a Secret Police very much in the vein of Gestapo , Kempatai , Stassi or KGB, albeit supposedly "privatized". I wonder what the American version of this "privatized" Secret Police will be called.
P.S.S : What would be a Big Business run USA dictatorship foreign policy would be like I Wonder? Would it be steadfastly isolationist , except when assess to markets are involved ? In that case , they might have a huge issue with any British Blockade on any warring powers in any WWI analogue. Or are they expansionist , seeking the direct annexation of other states , so as to fully secure and capture captive markets ? Without any Social Welfare at all , I foresee many Latin American coups ending with applications by Latin American Elites into the USA as states . And since the peasants of Latin America are considered inconsequential ,we just need to have elites to be seen as sufficiently Americanized to be incorporated into the US System.
Finally , I suspect that Nihilism , Nietzche's Philosophy of the Ubensmech and Atheism be rife among the elites of America .