Taking into account that the Borgia family were Valencians (and thus "Spaniards", although they came from a different kingdom than Castille so they had no place in America, but who cares), that the Knights Hospitalier of Malta stablished a (short-lived) colony in the Caribbean, that the Pontifician States sent troops to fight in Ireland and that Cesare was literally a conqueror (I think Machiavelli hoped that he would at last unite Italy), your concept is quite credible. Keep it moving!