I'll huff and I'll puff...
I don't believe the US is in a corner, this seems one big smoke screen for a failed MIC. They cannot take the chance that an S300 could drop an F-35, and thus they never intended on any military solution. I think its just showmanship and tough talk for the benefit of their corporate sponsors plus a hope that Venezuela would crater on its own through fear of impending doom. While the US regime sounds tough, its just bark, at this point. Because for reasons of image, they cannot sustain a loss and can't engage any government with any semblance of functional air defence.
RE: Venezuela Crisis: U.S. Has Painted Itself Into Corner