They can’t, of course. A subsequent Congress could repeal the clause requiring a super-majority to repeal it.
No, they can’t. The Constitution only requires a majority of the senators present (provided there is a quorum, of course). Any attempt to require a future Senate to meet some sort of “super majority” is unconstitutional.
Republicans are counting on us here to put them back in a leadership position. Unless they start now stating that they will repeal this monster, I will not contribute a nickle to the RNC or vote at all.