The best investing strategy during periods of geopolitical strife is to have no strategy at all, said Jeff Sommer in The New York Times. Rather than “panic about what the Iran war may be doing to your investments, try to forget about all of it.” That’s been “the standard long-term investing playbook for times of crisis,” and it still applies today, even as global markets whipsaw on the latest news developments. According to market researcher Jeffrey Yale Rubin, there have been seven major U.S. military campaigns since Operation Desert Storm in 1991. “One year after the start of these conflicts, the S&P 500, on average, rose 12.5%.” Investors who fled to cash missed out on those supersize gains. That’s a good “case…