This adaptation of The Grapes of Wrath brings the piece into direct conversation with our times in a way that allows the novel to live and breathe in a theatre as opposed to being studied as an artifact from another time.
While we are indeed currently politically divided and somewhat polarized, this is actually our normal state as a nation -- and on the polarization scale, we're nowhere near the "most divided" we've ever been. Far from it.
Lincoln's preservation of the union would not have been possible without his economic reform. It is the philosophy at the base of those achievements that must be the prototype for change in America now.