A MILITARY BASE IN POLAND (Reuters) – The top U.S. general cautioned on Sunday it was still unclear how Russia might react to the latest battlefield setbacks in Ukraine and called for vigilance among U.S. troops as he visited a base in Poland aiding Ukraine’s war effort. “The war is not going too well for Russia right now. So it’s incumbent upon all of us to maintain high states of readiness, alert,” U.S. Army General Mark Milley, chairman of the Joint Chiefs of Staff, told reporters in Warsaw following a visit to a base hosting U.S. troops. Reuters was asked not to publish the name of the bas…