No they won't. For one thing, we will still be a democracy (a republic is a limited democracy). So we can use ballots rather than bullets or riots to change our government if we don't like it.
For another, as soft socialism is implemented more and more Americans will have access to affordable housing and healthcare. Further, deep recessions that we have with capitalism will be smoothed out so that, although they won't be eliminated, they will be less intense and last shorter periods.
In other words, with soft socialism a lot of the ills that people riot about will be eased or eliminated. So there'll be no reason to riot