In the War of 1812 six American Frigates gave the Royal Navy all they could handle because the RN was involved with France and their empire. In the 1860's the U.S. Navy was fast becoming a first-rate navy with a lot more than six frigates. It is not conjecture to say that the U.S. Navy of the mid-1860's would have given the Brits fits.
I know this is a while ago, but I thought it would be interesting - did the USN wield more frigates in 1862 than in 1812, let alone "a lot more"?
In 1812 the US Navy disposed of the frigates Constitution, Constellation, United States, Chesapeake, Congress, President, Adams, Boston, Essex, New York and Macedonian. Total eleven.
In 1862, the US Navy disposed of the steam frigates San Jacinto, Mississippi, Susquehanna, Powhatan, Wabash, Roanoke, Colorado, Minnesota, Niagara. Total nine.
It happens that five of the 1862 frigates were "first class" (Wabash, Roanoke, Colorado, Minnesota, Niagara) while at least six of the 1812 frigates were.
The only way to count the USN's frigate line as being larger in 1862 than in 1812 is to include pure sailing frigates in the 1862 count; against a Royal Navy that would take the very last of her pure sailing ships out of service that very year, this comparison is disingenuous.