A married couple goes through divorce according to American laws. Is this divorce valid under Islamic laws?

Legally speaking the right to divorce is entitled to the husband in the original state of the matter. So he has the right to terminate the marriage contract by divorcing the wife. The majority of jurists recommended the presence of witnesses and based on this recommendation non- Muslims are allowed to be the witnesses of this divorce. The reason behind the allowance of non- Muslims to act as witnesses of divorce is that they are not initiating the divorce nor have a legal authority over the husband. They merely stand as witnesses to prove that this divorce occurred in their presence.

It is stated according to the asked question that the husband divorced the wife with his own will and had non- Muslims as witnesses to this divorce and this makes the divorce legally eligible according to the Islamic law.