Show up at a party or event just so people will see you and think you actually care about what's happening.

Probably from the days of gunboat diplomacy when warships would appear in foreign harbors to show that Great Britain, or some other colonial overlord, had a vested interest in the place.
I didn't really want to go to my cousin Noreen's birthday party, but I decided to show the flag and put in an appearance.
by Rile Crumble November 5, 2013
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