Ron Brownstein: “The latest ideas from President Donald Trump and congressional Republicans to reconfigure the Affordable Care Act face the same dilemma that every GOP alternative has confronted since Trump’s first term: The plan would impose its greatest costs on key groups within the Trump-era Republican electoral coalition.”“With the approaching expiration of enhanced subsidies that help Americans buy insurance through the ACA, Republicans are staring down the political threat of large premium hikes for up to 20 million people and the loss of coverage for millions more. In response, Trump and key congressional Republicans have proposed to convert all or part of the ACA subsidies into direct payments to individuals to pay for health care.”“That approach could initially benefit younger and healthier consumers. But most experts agree it would increase costs and diminish access for older, lower-income and non-college-educated people with greater health needs. And those older, working-class families are now more essential to the Republican than Democratic electoral coalition.”