Do you agree with this analysis that united states v nixon expanded the power of the presidency? why or why not?

I do not agree.

Nixon has exceeded his privileges as president.  

Police arrested five men for breaking into the Democratic Party national headquarters in the Watergate building in Washington, the capital of the United States. Two reporters from the then-small Washington Post, Bob Woodward and Carl Bernstein, decided to investigate the assault on the Democratic Party headquarters and found the link to the White House, the seat of the US government. They found out that the president knew about illegal operations. After the arrests, Nixon had secretly ordered his subordinates to cover up the Republican Party's involvement in the crime. The Republicans had hired the five men to spy on the Democrats.

The Senate began investigating the Watergate Case in 1973. The following year, documents emerged proving that Nixon had ordered the cover-up of the incident.

because mexico wanted to choose a centralized location

the answer is a new goverment.