@darius @cj my long-time strategy recommendation:
Kick off a liberal movement branded in conspicuously pro-America terms, undergirded on the totally true principle that most rightwingers' ideologies are antithetical to the symbols they invoke. Co-opt everything, including e.g. the Pledge of Allegiance ("liberty and justice for all").
To rub it in, call it something like the "Real Patriot" movement.