To help you understand what's going on in business and technology and what we expect to happen in the future, our highly experienced Kiplinger Letter team will keep you abreast of the latest developments and forecasts ( Get a free issue of The Kiplinger Letter or subscribe ). You'll get all the latest news first by subscribing, but we will publish many (but not all) of the forecasts a few days afterward online. Here’s the latest… (Image credit: Getty Images) The Iran war has reinforced a new fact of life: The importance of drones in modern warfare. They’ve helped Tehran hold out against Washington and allowed Ukraine to hold its own against Russia. The Pentagon is now trying to play catch-up as the U.S. prepares for a possible great-power conflict. Consider this simple cost comparison. Iran has forced the U.S.…