> So, its not exactly a mystery where he got the idea he could just invade neighboring countries with no consequences.

IIRC, an apparently poorly considered
remark by US Ambassador to Iraq April
Glaspie on the US position on Saddam's
dispute with Kuwait was a biggie.

The joke, and maybe the truth, about
the Dick Cheney remark that there was
"no doubt" Saddam had weapons of mass
destruction was that, of course he
had such weapons (poison gas) and
of course we knew he had them because
we "still had the receipts" from
when we sold that gas to him.
Of course we wanted Saddam to use
that gas against Iran.

IMHO it now appears that Dick Cheney,
the neo-cons, etc., had an idea about
the world and, especially, Iraq:

(1) Saddam was a bad guy. So,
push on him, and if he doesn't
obey, then invade him.
We pushed; Saddam didn't obey;
W and Co. invaded him in
Gulf War II.

(2) Then part of the idea was W's
statement "The Iraqi people are
perfectly capable of governing
themselves.". So, with such
thinking, the US rushed to set
up a government -- democratic,
constitutional, parliamentary,
secular.

Apparently the US expectation was
that quickly the US would leave and
Iraq would be liberated,
free, relatively independent,
peaceful, prosperous from the oil,
and a buddy of the US.

Then a reality check set in: Oops,
nope. Instead we learned what
Saddam had warned us about, that
we would have one heck of a time
holding Iraq together. Saddam,
with Stalinist techniques, had
held Iraq together, but without
Saddam what we did there just
let the place come apart.

Apart? Nearly every street thug,
gang leader, ambitious politician
or cleric, international opportunist,
etc. saw the fertile ground and
started up. Soon there was the
insurgency, i.e., something
between just chaos and a civil war.

A big trigger? One of the first things the US
administrator in Iraq, Paul Bremer,
did was to disband Saddam's army.
Hmm .... That army had ballpark
7 million men. Let's see:
IIRC, Iraq had ballpark 35 million
people so 17.5 million males.
So, the 7 million men was
essentially all the men of military
age in the country -- all of them.
Hmm.

So, right away Bremer just put
all 7 million
on the streets, broke. Uh, maybe
we might have thought a little about
just why Saddam had those 7 million
men in his army? Maybe mostly to
keep them under his control and off
the streets?

In particular, as the army was
disbanded, Saddam's huge weapons
supplies were left unguarded, then
stolen, then used in the insurgency,
e.g., as roadside bombs that
killed/injured a lot of US soldiers.

The main reason for the insurgency?
There are three
main populations in Iraq,
Sunnis, Shiites, and Kurds. They
all hate each other.
At least the Sunnis and Shiites
have been at war with each other
for over 1000 years.

And now, Iraq is essentially partitioned
into Kurd, Sunni, and Shiite areas.

The Shiites have Baghdad and
south and east from there
to Iran, the Persian Gulf,
Kuwait, and Saudi Arabia.

The Sunnis have the area north
and west of Baghdad and
extending into northern Syria,
and that Sunni area is mostly
under the control of fundamentalist,
medieval, brutal, angry, hostile,
ambitious
ISIS.

The Kurds have their areas, mostly on
both sides of the border of
Turkey.

Iran? Shiite.

Saudi Arabia? Sunni.

Assad in Syria? A branch of Shiite.

The rebels in Syria? Sunni.

The civil war in Syria? Apparently
just another chapter of the
1000+ year old Sunni-Shiite war.

What's different since 100 years ago?
There used to
be a lot of desert and not
much money or many people --
few people, poor, separated.
Now with the oil money, the desert
is still there but there is
lots of money and many more people.
So, the old Sunni-Shiite
war can draw lots more blood.

So, that's what W, Cheney, the
neo-cons, Wolfowitz,
and Bremer took the US into.
They were going to dump Saddam, set up
a secular democracy friendly with the
the US, and leave, all quickly.
Lots of thugs quickly saw the
fatal flaws, but W and Co. didn't.

So, the US spent lots of precious
US blood and treasure chasing
the dreams of Cheney, W, etc.

Lesson? If the US wants to play
a role in a swamp, then it needs
to understand the reptiles --
snakes, alligators, etc. Else,
can get bitten by the snakes and
alligators.