Ask the US Joint House Security Committee, or all of the nineteen US Security and Intelligence Agencies who separately identified Saddam Hussein's Iraq as the nation posing the greatest threat to the United States of America, her interests and her allies. All of whom got it wrong of course. You forgot to mention that bit.

Have you not noticed the USA has a long history of invading people and sometimes democratically elected leaders?

Since 1960..........

Bay of Pigs 1961
Dominican Republic 1965

Vietnam (1959 - 1974) Bit far away to pose a threat weren't they?
Still the domino theory said if they won the world would collapse and "no longer be safe for democracy". Well they won with no visible effect on democracy, apart from a couple of million dead in the area, widespread use of chemical defoliants - carpet bombings of civilans etc etc...and the 58,000+ dead Americans. But American governments love spending money on war.

Overthrowing regimes or installing puppet regimes in Indonesia, Guatemala, backing the right-wing regimes in El Salvador, bombing Libya.

CIA overthrowing a democratically elected regime in Chile. Come to the UK and take a look at my friend Luiz's scars where Pinochet's thugs tortured him.

Invading Panama 1989 and overthrowing Noriega. My that did a lot to stop drug-running didn't it!

Reagan even managed to upset his best (possibly only) friend Mrs Thatcher by invading a Commonwealth state. My those heavily armed Grenadans posed a real threat to the USA didn't they? Was it their armed aircraft carriers? Nuclear submarines? Supersonic Bombers?

Or did they just invade a tiny island in the Caribbean because they could?

Countries are invaded on a whim, nothing to do with threats to the USA and their allies. Often to overthrow a regime the USA simply doesn't like or to protect US big business.

Give it a rest old boy - I am afraid history in not on your side.