Some American institutional investors, in pushing for the highest returns, could soon find themselves hanging by their own rope while destroying the country, critics warn. That’s because several big American money managers are investing through retirement funds in China, according to critics who say there’s good reason for these investments to be reviewed. They contend American dollars fund Chinese venture capital firms, undercutting American businesses and violating human rights. “Can anyone explain to me why the Maryland State government is helping tech startups in China to compete with U.S. companies? MD pension fund invests in Chinese government-influenced VC fund,” Rob D. Atkinson, president of the Information Technology and Innovation Foundation (ITIF), wrote on Twitter recently. ITIF is a D.C.-based technology think tank. Maryland State Retirement & Pension System, in a December filing with the Securities and Exchange Commission, reported that it increased its stake in Yum China Holdings Inc. “by 3.4 …