That song is what soccer fans sing at games to support their teams. it's sung in English even in other countries.
Nothing special about it. Just a spirit booster.
> I don’t understand why POTUS complimented Feinstein
It counters the MSM fakes that are just mentioning one party. He can't criticize them for just blaming Republicans if he goes with moral equivalency by blaming Feinstein.
So he says, "Feinstein was mentioned, too, but I find her honorable". That implies the two pubs are honorable, as well without looking like he's just trying to make excuses for his own party.