In actual practice, the US applies "Common Law" quite generally in all matters not specifically limited by our US Constitution (and by individual State Constitutions except in Louisianna which uses "Napoleonic Law" for their court processes and other legal forms).
There are naturally some differences between the US and UK application, but early development of the US "traditions" and case history quite commonly cited the UK common law, and such references still appear and are generally accepted in legal arguments in US courts.