Also because "good" democratic governments that respect human rights and personal freedoms deteriorate to oppressive tyrannies all the time. What's to say that your country won't?

Who'll protect you when they come knocking on your door to talk about that thing you posted about somewhere online, which used to be quite legal and no problem, but now is super illegal for some oppressive reason or another?

    First they came for the socialists, and I did not speak out—

         Because I was not a socialist.

    Then they came for the trade unionists, and I did not speak out—
         Because I was not a trade unionist.

    Then they came for the Jews, and I did not speak out—
         Because I was not a Jew.

    Then they came for me—and there was no one left to speak for me.