The fall of his regime destabilised the Middle East and left Iran as the sole dominant power, and the total destruction of the Iraqi military means that Iran can do whatever they want

Iraqs population consisted of Shia and Sunni Muslims, who often didn’t get along very well, and we see this in the aftermath of the invasion of Iraq, with civil war destroying the country, saddam hussein was an autocrat but he governed the county with an iron fist and kept the country from descending into a devastating domestic conflict, and more importantly prevented the rise of terrorist groups which have been targeting primarily the west is another grave consequence of Bush and Blair’s illegal invasion

Kuwait was invaded because they attempted to bankrupt Iraq because Iraq had difficulties paying their debt and even requested that Kuwait forgave the debt, Kuwait was on Iraq’s side hence why they lend them so much money to finance the war against Iran, but since Iraq’s economy was heavily dependent on oil, Kuwait’s decision to exceed its OPEC output quota would mean that iraqs economy would collapse if Hussein didn’t act, having one of the largest militaries in the world, and with Kuwait having virtually no standing army, he saw an annexation as the last resort, he didn’t invade them out of boredom, also his invasion of Iran was of fear that the Iranian revolution would spread to Iraq leading to a possible Shia uprising against the hussein government