A proposal that would send $3,000 cash payments to millions of Americans gained momentum this week after the nation’s largest nurses union formally endorsed the legislation. National Nurses United (NNU) announced its backing of the Make Billionaires Pay Their Fair Share Act , a bill introduced by independent U.S. Senator Bernie Sanders of Vermont and Democratic U.S. Representative Ro Khanna of California. If passed, the law would impose a 5 percent annual wealth tax on U.S. billionaires and use