He thought it was misguided, unconstitutional, and treasonous to the country.
The die is cast means an event has happened or a decision has been taken that cannot be changed. It is also a variation of a Latin phrase attributed by Suetonius to Julius Caesar on January 10, 49 BC, as he led his army across the Rubicon river in Northern Italy.
Today, the phrase crossing the Rubicon is an idiom that means to pass a point of no return.
I think it’s false but I’m not 100% sure
Well, the British was the cause of James Monroe passing the Monroe Doctrine. They settled in territory they weren't permitted and then the Monroe Doctrine was passed in effect of European settlement aka the British. They then agreed to not settle and in return, their foreign affairs was left to be.