Remember this, take it to heart, live by it, die for it if necessary: that our patriotism is medieval, outworn, obsolete; that the modern patriotism, the true patriotism, the only rational patriotism is loyalty to the nation all the time, loyalty to the Government when it deserves it.

Mark Twain (1835-1910) American writer [pseud. of Samuel Clemens]

Story (1905-02-02), “The Czar’s Soliloquy,” North American Review, Vol. 180, No. 580 (1905-03)
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Advice that Russian mothers should be giving their children.

Sometimes paraphrased: "Patriotism is supporting your country all the time, and your government when it deserves it."