U.S. stock markets find renewed optimism as falling crude oil prices ease inflation concerns, while investors closely watch diplomatic developments between Washington and Tehran. After months of uncertainty surrounding geopolitical tensions, energy costs and the direction of the global economy, investors are finding fresh reasons for optimism. U.S. stock futures and major equity indexes have moved higher as oil prices declined amid developments surrounding potential talks between the United States and Iran. The market reaction reflects a familiar relationship between energy prices, inflation expectations and investor confidence. When crude oil becomes cheaper, businesses and consumers may face less pressure from transportation, manufacturing and fuel expenses. For Wall Street, the possibility of reduced tensions between Washington and Tehran offers more than diplomatic encouragement. It raises hopes that energy supplies could become more predictable and that one source of economi...