Describe the Watergate scandal during Nixon's presidency and assess its short-term and long-term impact on American politics.

In short, the Watergate scandal can be described as follows: President Nixon, concerned that he would lose his reelection bid in 1972, authorized operatives to break into the Democratic Party headquarters at the Watergate Hotel in Washington, DC, to see what they could find and steal to help the Republican campaign. The break-in and burglary were bungled, and evidence strongly indicated that the president was involved in the event. This led to impeachment hearings, for a United States president takes an oath of office to uphold the law of the land, and Nixon clearly violated the law if he authorized a break-in and robbery. As the hearings went on, it became clear that Nixon had known about the burglary and worked to cover it up. When this evidence came out, Nixon's supporters abandoned him, and he chose to resign.
In the short term, the Watergate hearings riveted the nation, while Nixon's resignation and his subsequent pardon by the new President, Gerald Ford, brought closure to a sorry event, even though the pardon (understood as a "deal" for Ford to get the presidency) is widely believed to have cost Ford the 1976 election.
In the long term, the Watergate scandal contributed to the political polarization of the United States. Many on the right were angered at what they thought was the partisan scapegoating of Nixon for "business as usual" dirty politics, while those on the left were outraged that a sitting president could so easily disregard and break the law of the land. The long-term effects have led, for example, to the tit-for-tat impeachment of President Clinton for lying about his affair with Monica Lewinsky, and to heightened tensions between liberals and conservatives.