English lesson in the Senate

What is the difference between leave and Vacation. The Senate did a good job trying to decide whether the president is on leave or on vacation, both grammatically and constitutionally. I would have loved to tell you the difference but I am even more confused and am thinking of going back to school. The only thing I can deduce is that Mr VP is not acting President. Senator Sekibo also gave us a long lecture about what is meant to transmit to the senate by the president. The video of that sitting will make a nice movie