Tokyo stocks retreated Tuesday, with the Nikkei stock index closing at a six-month low after diving more than 2 percent at one point due to concerns that Japan may not be immune to U.S. President Donald Trump's tariff policies.The 225-issue Nikkei Stock Average ended down 235.16 points, or 0.64 percent, from Monday at 36,793.11. The broader Topix index finished 30.04 points, or 1.11 percent, lower at 2,670.72.On the top-tier Prime Market, decliners were led by nonferrous metal, securities house and service issues.The U.S. dollar briefly weakened to the mid-146 yen zone in Tokyo, as the safe…READ FULL ARTICLE