a war waged for what is supposed or proclaimed to be a holy purpose, as the defense of faith.
any disagreement or argument between fanatical proponents of radically differing beliefs, opinions, etc.:
a holy war on the merits of rival computer operating systems; a holy war about welfare reform.
a war waged in the cause of a religion
Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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There's almost no way to write about this subject without starting a holy war.
When it began last fall, it was the political equivalent of holy war.