Jordan made a huge mistake when it decided to join the fight against Israel during the 1967 Six-Day War.
In June of 1967, Israel launched a war of defense against the Arab states bent on its destruction and achieved a stunning, miraculous victory, including the liberation of Jerusalem.
While Jordan initially didn’t take part in the war, they did join shortly after it began.
This video explains why Jordan joined after Egypt, including the details of why it was a huge mistake on Jordan’s part.