Sentence:  "We assume that a dangerous brinkmanship, a <WSD>war of nerves</WSD>, is under way, but it will not grow into a hot war," the official told Tass. 
Meaning of the word marked with <WSD> tags:  A situation in which opposed parties refrain from direct conflict but maintain a tense, contentious relationship in which each uses annoyances or intimidating psychological tactics to attempt to dishearten and unnerve the other.