I currently hold the JAL USA card. It is mostly intended for people who recently moved to USA, and do not have long credit history (I managed to get a credit limit on the JAL USA card that is more than 5x higher what I could get from a standard US bank because of lack of credit record in US, which was very helpful in the beginning). Personally everything about the card is very average, the reason why I keep it is because you get 10% mile bonus on every JAL flight (based on the flight distance, not based on your actual accumulated miles). For example, a flight from Tokyo to US east coast is around 7000 miles and you will get 700 miles bonus for that from holding the JAL USA card. If you do a few such round trips a year it could add up quite quickly!
They had a 15000 miles signup bonus for a long time, and a 5000 miles bonus on your first JAL international flight (20000 bonus miles). Once in a while there are some offers but nothing too exciting. Totally agree that the foreign transaction fee is stupid, definitely use another JAL card for inflight shopping or duty free...