党同伐异

党同伐异 [dǎng tóng fá yì]

1. ■ （无原则地分立门户派别， 偏袒同党， 攻击异己） defend those who belong to one's own faction and attack those who don't; be narrowly partisan; close ranks against aliens; discriminate against people who disagree with oneself; get rid of those with dissenting opinions; side with one's copartners against those who disagree; support one's own party and attack the others; take sides with those in the same cabal and ostracize those who hold different opinions; unite only with those of the same ideas and attack those who differ