After going through all the time, trouble, expense, gigantic risk of 9/11, the US decides NOT to plant fake WMD evidence in Iraq.

As a result, the US ends up looking like complete idiots.

Weapons have signatures and can be traced just like the Anthrax and nukes. They have high levels of specificity. There are lots of watchdogs in the world and that would be way too risky. That is why they have destroyed weapons caches in Iraq that were stockpiled and acquired by many countries including USA defense contractors.

Why do you think they lied about WMDs and never produced them?

Weapons have signatures and can be traced just like the Anthrax and nukes. They have high levels of specificity."
A WMD is not a specific type of weapon. It is a description of any kind of weapon that will cause mass destruction.

"There are lots of watchdogs in the world and that would be way too risky."
I thought the US paid off everyone to help cover up everything?

"Why do you think they lied about WMDs and never produced them?"
I myself do not know if they lied or just relied on poor intelligence. They never produced them because they were not there.

As far as things, like weapons, being traced - many of the things that would be necessary to pull off a US government conspiracy would be traceable as well.

Looks like you thought wrong.

Such as??

Such as whatever it is that is causing them to initate and maintain a massive cover-up.