International BA to Operated by AA…

A couple months ago I booked on the British Air website round trip business class seats that included flights from Chicago to London and back. I specifically chose flights that were operated by BA because their quality of service is usually superior to other airlines. Today I received notice that our return flight has been changed to a “operated by American Air” flight in business class to Dallas. My experience with AA has never been positive. Do I have grounds to get it changed back to a BA flight if I called BA customer service, or am I stuck it? Is there any recourse? Anyone have any recent experience with international flights on AA in business class? My wife tells me we should probably just accept the change because we have a moron for a president who started an unnecessary war in the Middle East that created havoc for the airline industry. Suggestions?