I am not saying that they were in charge. What I am saying is that the fascists supported big businesses and cultivated them as a base of support in opposition to the traditional socialist base of support- the industrial workers. Their policies were ultimately ruinous for business, but the thought was that ultimately businesses were important for a nation as a whole and should be supported at the expense of workers. No one could have predicted how horribly disastrous Hitler's foreign policy would end up being for German business; indeed there was a time that it seemed as if Germany would rule all of Europe.
And what I'm saying is that Fascists usually came from the ranks of workers (and also from the middle class), much more than from big business. They were not aliens enlisted by Big Business to subdue the working class. They were not astro-turfed figureheads. They were the people in charge.
The thought that Mussolini or Hitler were pawns of Big Business is completely ridiculous. They valued Big Business as long as it was useful for their project. They used Big Business, not the other way around.
And a lot of people did predict exactly just how ruinous Hitler and Mussolini would be. Including a lot of businessmen and bankers. If anything, the shock was that it took so long for disaster to arrive. Simultaneously fighting Britain, the USA and the USSR, how could this possibly be good for business?