Some legal experts say even though no shots have been fired, Ukraine has a potential case that Russia has already committed an act of aggression, given its show of military force and takeover of part of another nation’s territory. “Most importantly, consider the implications for the charter if the answer were that this were not an armed attack: Ukraine could not lawfully use force against Russian troops to protect territory that undisputedly is part of Ukraine,” writes Ashley Deeks of the University of Virginia Law School on the legal blog “Lawfare.”