The atrocities of the Saudis in a variety of situations are well documented. It's also no secret that the majority of the terrorists on 9/11 were Saudi. Occam's Razor indicates it was probably the Saudis, or a Saudi terrorist organization, that was behind the 9/11 attacks. There is also plenty of documentation to show that the people of many Middle East countries were happy it happened, whether or not they were involved.
As for the terrorism comment, I barely even spoke of it in this comment, and where I did, I mentioned America being very scattered on what they call terrorism. If you're referring to other comments I've made, I've generally been against them, whoever commits them. Some may see me saying an event was unsurprising, predictable, or even inevitable as supporting, but that's a failing on their part, and perhaps yours. I'm not happy Russians are getting killed in Ukraine, but I absolutely support Ukraine's right to defend their sovereignty. I'm not happy with the Palestinian attack on Israeli targets, particularly civilians, but I'm not surprised it happened give the repression they've been living under for decades. I'm also not very surprised by Israel's response, but I would have been much happier if they had chosen a solution other than genocide to achieve peace.
If you think ideology is why the Iran war started (this time around) you should read back a bit. The last two regimes were very authoritarian, one was backed by the Americans, and the one before that was leftist and democratic, which explains why the Americans interfered. Clearly, America has no trouble dealing with authoritarians, whether in Iran, in Saudi Arabia, or elsewhere, so long as the money and oil keeps flowing. And resistance to America is less than the money flowing in, which is literally why Saudis got a pass for assassinating an American journalist (and Trump doesn't like journalists who actually do their job).