A bit over a century ago, millions of southern Italian peasants began pouring into the US. Not long after, they began to attempt to write themselves into the nation's history. We see this today with web pages like this one from the "National Italian American Foundation".
Analysis of the 1790 Federal census suggests about 90% of the ancestry of white Americans of that era derived from Britain, with Irish, German, Dutch, and French accounting for almost all the rest. All other origins taken together equate to 0.3% of the population . Needless to say, Italians did not play a major role in founding the United States.
Promoters of "Italians-American" pride are left primarily with two options: (1) outright lying (or, to be as charitable as possible, extreme wishful thinking combined with invention of fact), as we've seen with William Paca; and (2) claiming as "Italian" any figure with fractional (generally Northern) Italian ancestry.
Today, we'll look at a couple instances of the latter.
The NIAF say Declaration of Independence signer Rodney was of "Italian origin". They are about 1/64 right. Rodney's Italian ancestor, gggg-grandfather Julius Caesar Adelmare (WorldConnect pedigree), immigrated not to America, but to England--about 1550. Adelmare, whose origins lay in Treviso (near Venice, in northern Italy), was a physician to Queen Mary. I find it hard to locate in Adelmare or his gggg-grandson an argument in favor of mass immigration of Sicilian peasants to the United States--but maybe that's just me.
The NIAF are happy to claim as Italian anyone named "Taliaferro". Their list of "Italian officers in the American Revolution" contains two individuals bearing variants of the name.
The pattern should already be familiar. The first Taliaferro immigrant to America, Robert, was born in 1626 in England. His grandfather, born in Venice in 1530, had immigrated to England. Robert's ancestry was about 1/4 "Italian". His Revolutionary War-era descendants probably had "Italian" ancestry about as dilute as that of Caesar Rodney.
 Ales Hrdlicka. The Old Americans. Baltimore: Williams & Wilkins, 1925. pp. 9-10.