As far as I am aware, NO satisfactory solution - legal or otherwise - has been found so far, to achieve this.
He did not destroy it - he took it over. This was an ambition of his father Phillip II of Macedonia, however he was murdered and his son Alexander successfully took on the project. People don't want to destroy an empire - it is much more valuable and rewarding as a going concern. The government within the Empire simply changed. Alexander retained some of the existing Persian provincial governors, replaced others with Macedonian generals. But he was about establishing good government and prosperity, not destroying.
He took over the Persian Empire. He didn't destroy it as he wanted it in good condition for himself.
Alexander the Great invaded it successfully and converted it into an empire of his own.
The English Empire (and subsequent British Empire) were never successfully conquered since the country's inception.
pallavas
The Ottomans Empire
Greece
Codified the laws of their empire
the Aztec empire and the emperor of this kingdom was Montezuma
Cortes destroyed the Aztec Empire in Central America.
yes
The Romans had no ethics in expanding their empire - they wanted to eliminate a resilient rival for control of the Western Mediterranean and adopted the Nazi-style 'final solution'.