You missed the point.
Cruz made a point that Rubio was saying something different to spanish audiences than what he was saying at the debate.
Rubio intimated that Cruz had no idea what he said because he was relying on someone else interpreting. Cruz responded in spanish to show he did not need an interpreter.
The point was similar to what Arabs say to the english speaking press and what they say in arabic to their own people, not that speaking spanish was a requirement to be president.
The point was similar to what Arabs say to the english speaking press and what they say in arabic to their own people,
^^^^^
This. This is unforgivable.