By the time the post-war occupation had started to slog into a quagmire (the run-up to the 2004 presidential election), we had basically witnessed the dawn of our modern age.
No, it wasn't; Fox had done that before, and and MSNBC, to the extent it eventually did, didn't until much later (9/11 occurred during, and didn't end, the period where MSNBC and CNN were kinda trying to compete with Fox in the same ideological targeting even though CNN was consistently painted as the Left network by the Right, and MSNBC didn't acquire a fairly consistent “left”, or at least Democratic, editorial position until into Bush’s second term, as a gradual evolution from a mix of different editorial positions.
> and when political discourse on the internet started to really sour.
As someone who was online pretty continuously since when “political discourse on the internet” met Usenet, the idea that it started to sour only after 9/11 is silly. More people started interacting online around that time, but that was more driven by easy blogging platforms becoming available and internet access becoming more ubiquitous than 9/11 or any connected political actions.
True.
> Even a lot of the domestic political polarization and social crackup we see in America today can be traced back to the divisions that be Iraq War created.
Less true,IMO. There's a line through divisions over post-9/11 policy, but it doesn't really start there and there's not much specially about it; its pretty consistent with the trend of crystallization of the polar positions after the end of the long realignment period of the overlapping New Deal and Civil Rights partisan realignements in the early-mid-1990s.
If you look right around the gearing up for the Iraq War it may look like a big acceleration of divisions, but that's mostly unleashing what was deferred in the rally-around-the-flag effect in the immediate aftermath of 9/11.