This was the root of the overblown Kennedy gaffe where he said “ich bin ein Berliner” instead of “ich bin berliner.”
It emphasizes the statement if you ask me.
Only many years after learning of the speech I read online that it's allegedly "a gaffe".
(In case you put the emphasis on "ein", you would clearly emphasize that you are just one of the many Berlin citizens.)
That said, blunders do occasionally happen even at this level. During Bill Clinton's visit in Romania (the first time a US president visited the country after the Revolution), he said in a huge public speech that the American people stands shoulder to shoulder with the Romanians - which the translator for the public broadcast translated as "șold la șold", which sounds similar, but means "hip to hip" (the correct translation, which is also a literal translation as the expression exists in Romanian as well, is "umăr la umăr").