No, they weren't. Americans tried to imitate the European way of warfare but they failed. Look at the differences between the British in the Crimea and the Americans in 1861. They just didn't achieve the same level.
Cavarly and infantry barely meddled with eachother apart from dismounted fighting, which is a world of difference with the (succesful) charges at the Crimea.
I'm not saying Europeans were superior in fighting skills, but they were in the European way of fighting, which the Americans TRIED to adopt, failed, and then went on to develop their own style. European envoys to the war often pointed out the differences between the two ways of fighting and the results.