1. False. "At 2:45 a.m., Mateen called
News 13 of Orlando and said, "I'm the shooter. It's me. I am the shooter." He then said he was carrying out the shooting on the behalf of IS and began speaking rapidly in Arabic Mateen also said the shooting was "triggered" by a U.S.-led bombing strike in Iraq that killed
Abu Wahib, an IS military commander, on May 6." Source: wiki
2. While everyone you mentioned qualifies as a terrorist, there is a major difference in magnitude between the Islamist terrorists and everyone else. A white supremacist may carry out a mass shooting or a radical pro-lifer might bomb an abortion clinic, but they aren't murdering thousands of civilians at a time the way the Islamists have. And hopefully it stays that way.
3. I'm not the one who started trying to keep score. You erroneously claimed that Christian terrorists kill more people in the US than Islamist terrorists. 9/11 is a big reason why that statement is false.