To answer your question, "What was Nixon thinking with making the Nixon tapes..."

Richard Nixon thought that history would want to know everything about his presidency...what was discussed, options considered, and decided.

He implemented a recording system that came back to haunt him, when it came up during the Watergate investigation. The press and the nation were surprised to learn of the existance of a tape recording system.

But they weren't supposed to. No one was susposed to be aware of it.

Later, as the legal manuveuring tried to get those hours and hours of tape released, his staff apparantly tried to help him out, by intentionally erasing a selected portion of the tape. Unfortunately, they didn't realize that any magnetic erasure could be detected...and it was clear that an attempt at erasing the tape in that spot had been done at least five or six times until they got what they wanted.

That "smoking gun" was more than enough to turn public opinion against him/them.... and it was only a matter of time before the questions of "Who knew, when did they know, and what did they do about it" began to weigh so heavily, that he had little option but to leave office.

Others may have a slightly different opinion about how this ended or why, but the end is still the same.

President Nixon, a discretionary character, sought to determine what the Democrats at watergate were up to. The election was comming. Having the indiscretion of recording their private meetings and being caught by the News reporters left him with an attempted cover-up. He was exposed and the relentless press predated upon him and his staff. The papers and media effected every journalist the effective process of examining the ethics of that case. Haldeman was staff secretary and advised President Nixon that the press would have the election his loss and it skyrocketed to impeachment. What the deceased president was thinking can only be surmised. He probably didn't give much thought to the crisis until it got real with impeachment proceedings. Anyway, he was a good sport. God rest his soul and may it never happen again.