Somewhere between Peron's Argentina and Yugoslavia might be the closest any populist or leftist country has ever come to actually working; basically, anybody interested in future social or political systems is going to have to study these two one way or another, whether they be liberal or conservative or whatever.
What went wrong? One version:
Basically Perón failed because his reforms were not radical enough. For example, although he raised rural wages and forced landlords to sell cheap to the AIPE, he refused to take the next step when they balked. He did not nationalize the land. Thus, the amount of land under cultivation dropped from nearly 22 million hectares in 1934-38 to just over 17 million in 1955. What you had was a producer's strike, not that much different from the kind Allende was confronted by.
Of course, the example of Russia and what happened when a state simply took over farming had to have been fresh on Juan Peron's mind and the idea of 15M people starving to death in a place the size of Argentina likely impressed him as trouble he didn't need. The question is, what the hell should he have tried to do?
And then, the same source:
...The one thing that they can do to keep imperialism at bay is impermissible: to arm the workers and expropriate the expropriators. Despite their inadequacies, the workers movement has an obligation to defend such governments under attack from imperialism....
Now, granted Peron's problems were domestic and not related to Yankee imperialism and keeping in mind that in 1890 Argentina was an economic powerhouse roughly on a par with the US and not even a rational target for Yankee imperialism...
Nonetheless the boy appears to have hit the nail nearly over the head here. The operative idea is the US second amendment. The first thing which would have occurred to me to do in Peron's place would have been to go over to that big Imbel plant in Brazil, and order about 300M dollars worth of FAL rifles and 308 ammo and spread all of that stuff out amongst the "descamisados", and aside from any effect that might have had amongst the nation's rich landowners, it might also have served as a permanent bulwark against the recurrent military coups and banana-republic regimes.
I believe that the second amendment is an idea whose time either has come or should come all over the world. It might have done something for Juan Peron; it definitely would do something for the 70,000 people who get killed by snakes every year in India. That also would not be possible in a country whose people were armed.