“When Republican government isn’t able to improve the lives of their electoral base, I imagine those people will turn on them hard.”
Your statement above is exactly what will happen. That is what is supposed to happen. I would say that is what happened to a Democratic presidency. The people did not see/feel “their lives” improve under President Obama. They decided a change was needed, and former Secretary of State Clinton, did not offer them that change. America will be just fine, as long as the people continue/start to hold their elected representatives accountable.