In fact Saddam can get away of invading or occupying kuwait, US knows about it, and it is believe that there are secret communique between US and Iraq limiting the war on only capturing Kuwaiti Oil field and once they were captured, the Iraqi would have left. That would be enough for US to pay back what Iraqi think the US owe them during the Iran-Iraq war.
Now for reason beyond our imagination, this is not to be, the Iraqi troop occupied Kuwait and they actually trying to annex and dispel the Kuwaiti royalty, whats more is they (Iraqi) try to attack and invade the US moderate allied in the Kingdom of Saudi Arabia. That is the red line for the US to act, infact, hostility between US, Saudi and the iraqi have started long before the first gulf war.
Maybe Saddam took the US blessing too far or he think he can litrrally took Kuwait and then Saudi without any foreign intervention? Gods knows
It was a foolish gross miscalculation on his part.Kuwait is the second largest source of petroleum in the Middle East and so Iraqi invasion of Kuwait sent the world oil market into a frenzy. Iraqi forces then gathered their forces on the border with Saudi Arabia, the second largest supplier of oil in the world. This in turn brought the military might of the United States into the conflict. The shear fact that he had positioned the full force of the Iraqi Army to the border of Saudi Arabia, a key military and energy ally of the Civilized World, and a major supplier of oil to the United States -- inevitably placed the United States at odds with Iraq. It was a war that was brought on by Iraq.
In Fact --- the late Saudi King, King Fahd and Prince Khaled bin Sultan --- both lambasted Saddam for his decision to invade Kuwait, and lambasted him further for the threatening fact the latter had positioned the Iraqi Army at the border of Saudi Arabia.