It's not that the dots were difficult to follow so much as Bush and his gang didn't WANT to follow them.
There was sufficient intelligence showing that Al Qeda was planning an attack on the US. Bush either didn't understand or didn't believe thia was actually going to happen. The same was ture for Hurricane Katrina. The power and ferocity of the storm was no secret yet Bush didn't act. Bush has a misplaced sense of priorities. Not to mention he's a dumb ass.
The UN Commission had determined that Iraq had nothing to do with 9/11 and that Saddam had no WMD's. Nonetheless, Bush had a personal vendetta against Saddam and didn't care how many innocent lives he had to take to fulfill that vendeta.