Actually going to the site in question points out the following:
1.) It only measures sales of conventional weapons and not the chemical or biological weaponry that the United States did sell Iraq.
2.) Properly, it should be "weapons imported by Iraq, 1973-1990" because no government sold Iraq weapons after 1990. (The real chart is blank after 1990.) Adding the "-2002" is just a crude attempt to make it look like Russia was selling arms to Iraq right up until last week.
3.) A minor point, but worth noting, is that the lists are totalled by dollar value and not adjusted for inflation, which means the rapid inflation of the early 80s artifically inflates the figures for that time period.
4.) Incidentally, note that the primary offender on the list is a government that no longer exists. Furthermore, looking at the chart, the vast majority of arms imported by Iraq from foreign governments were destroyed in 1990 - it's mostly helicopters, jets, and long-range missiles, which were all required-destroyed (with a couple of exceptions Saddam managed to hide).
5. and most important) The chart is strictly a measure of government-to-government sales of conventional weapons. It doesn't measure, for example, the chemical or bacterial supplies American companies sold to Iraq. It doesn't measure much of anything America sold to Iraq, because American defense contractors are allowed to sell directly to foreign nations, whereas in France defense contractors have to sell through the government, and the USSR sold directly from the army. Oh, and it doesn't measure military aid given to Iraq by the United States in the form of cash, and the US gave Saddam a lot.
It's just a weak attempt to evade the United States' responsibility in arming Iraq by distorting the facts and ignoring others.
This would've made the news with or without Cat Stevens, Eddie. But if it was some random muslim guy who was on the terror watch list and not Cat, people would be ranting about how we didn't manage to stop him BEFORE he boarded the plane.