Casus belli

rise to war, escalation to war

Casus belli is a modern Latin language expression meaning the justification for acts of war. Casus means "incident", "rupture" or indeed "case", while belli means "of war".It is often misspelled and mispronounced as "causus belli" since this resembles the English "cause" (and a different Latin word, causa {cause}). "Casus belli" is also pronounced this way because the term is used with the meaning of "cause for war", instead of "case of war" (notice that "case" comes from Latin "casus").
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Noun
1. an event used to justify starting a war
(hypernym) beginning

casus belli, rise to war, escalation to war

n. casus belli, rise to war, escalation to war