BRUSSELS — NATO Secretary-General Mark Rutte warned on Thursday that a Russian victory over Ukraine would undermine the dissuasive force of the world’s biggest military alliance and that its credibility could cost trillions to restore. NATO has been ramping up its forces along its eastern flank with Russia, Belarus and Ukraine, deploying thousands of troops and equipment to deter Moscow from expanding its war into the territory of any of the organization’s 32 member countries. “If Ukraine loses