The statement 'Yep.' is a brief affirmation in response to a tweet by @ChrisMurphyCT, which discusses the use of tariffs as a political tool rather than an economic policy. The original tweet by @ChrisMurphyCT constitutes public discourse as it addresses a significant public issue related to economic policy and its implications for democracy. However, the response 'Yep.' itself does not engage substantively with the public issue or contribute to the civic dialogue. It merely indicates agreement without further elaboration or analysis.