Mitzvah to demonstrate

Parshas Hashavua                     הוכח תוכיח את עמיתך   part 1 The Mishna Verurah (ביאור הלכה תר"ח) writes that there is no חיוב להוכיח someone who is a מחלל שבת בפרהסיא. On someone who is a מחלל שבת שלא בפרהסיא, the M.V. is not sure if there is a חיוב להוכיח. According to the MV. We would not be allowed to demonstrate in Eretz Yisroel on Shabbos. Since you are not obligated to demonstrate against מחללי שבת בפרהסיא, therefore, you may not be the cause of חילול שבת by having the police drive to the demonstration etc. part2 Harav Hagaon R. Moishe Shternbuch Shlita (תשובות והנהגות ח"ז ס' מ"ב)  writes: " The purpose in demonstrating against חילול שבת is not for their sake, to stop them from חילול שבת. They will not stop their חילול שבת because of our demonstrations. The purpose of the demonstrations is for our sake. Their חילול שבת harms us in a number of ways. (חינוך הבנים -חילול השם etc,) If we don't demonstrate they might expand with their חילול שבת. Therefore to demonstrate is a Mitzvah*. Based on a Teshuvas Mahril Diskin, we are not concerned that by doing so we will be causing more חילול שבת by them transporting on Shabbos the police, the press, etc. to the demonstration.  *Not the Mitzvah of הוכח תוכיח but קידוש שם שמים etc.