Elizabeth was President by 1777, when she presided over the infamous Country or Kind? debate. She had the Great Meeting Chamber at MACUSA headquarters in Washington expanded to fit the many witches and wizards from America who wanted to attend.
The debate was held to reach an agreement on whether or not to intervene in the Revolutionary War being waged by the No-Maj community. They discussed whether to join them or whether they should not intervene as it was simply not their fight. When they could not reach a consensus, Elizabeth sought the advice of the British Ministry of Magic to find out whether they were planning to intervene. They replied with a simple four word message stating "Sitting this one out". Elizabeth sent an even shorter reply back, stating "Mind you do." Neither MACUSA or the Ministry of Magic intervened in the war.
Notes and references
|Magical Congress of the United States of America|