The former commander of the U.S. Central Command, Gen. Frank McKenzie, has raised the alarm over the escalating threats that ISIS and its subsidiaries pose to the United States. What Happened: McKenzie, in an interview with ABC News, voiced his worries over the growing ambitions of the Islamic State terror group to target the U.S. and other foreign nations. The retired General cautioned, “We should believe them when they say that. They’re going to try to do it.” McKenzie pointed out that the threat from ISIS-K, an ISIS affiliate, has intensified following the group’s claims of responsibility f…