Bob
No cover up at all, bar the fact that Bush Jr didn't make use of the fact that Iraq had failed to give up All WMD stocks as specified in the original UNSCR for the ceasefire in 1991. If you read this book, you will see the efforts that Saddam took to hide WMD related equipment.
Written by a Brit who was on the UNSCOM Bio weapons inspection team, he is quite blunt on his conclusions on why things turned out in Iraq the way they did up to 1998. UNSCOM pretty much got the shipping manifests for all of the WMD and dual use material shipped to Iraq throughout the 1980s. Every man and his dog was selling Saddam something or other that could be used for the production of WMD. When UNSCOM was kicked out in 1998, there was still a lot of stuff that hadn't been accounted for