It’s a fine line and there must be a difference, otherwise there won’t be two words.
How the founders relate to adolf is beyond me. OTOH some would argue adolf was being patriotic (mostly these are on the conservative side of life), others say he was a nationalist (these tend to be left spinning), i just say adolf was an evil human being.
One possible distinction is found in that fact that Nationlism is a Procrustean mold to which all must conform, whereas Patriotism still respects individual expression and dissent.
Thankfully history doesn’t repeat itself.
Sorry for getting snarky.