The billionaire explains his network’s shift away from partisan politics at a philanthropy summit. : Charles Koch speaks at the Koch donor network seminar in Indian Wells, Calif., in January. (Seminar Network) THE BIG IDEA: Charles Koch doesn’t just think President Trump’s threat to close the southern border is terrible. He’d do the opposite. “I would let everybody in who comes here to contribute, and no one who wants to come here to do harm, and see how easy this is,” the billionaire industrialist said on Monday in Redwood City, Calif. “This goes to our whole philosophy of openness.