The US is a federal, presidential system. It is federal because it is a union of fifty individual states and power being separated between the states and their federal government; presidential because the head of the federal government, the President, is also the head of state of the US. The President is elected by the people of the US every four years and can, by law, serve only two terms. In 2020, Joe Biden was elected as the 46th President with 51.4% of the popular vote and 306 Electoral votes (Trump received 46.9% of the popular vote and 232 Electoral votes). Four years before, in 2016, the Republican candidate, Donald Trump, beat the Democrat, Hillary Clinton, to become the 45th President. Clinton lost in spite of beating Trump in the popular vote by some 48% to 46; 66 million votes to 63 million. This was because US presidents are not elected by a vote of the people across the US, the popular vote, but by the Electoral College vote of each of the fifty states. Each state has a number of Electoral College votes based on the size of their population: Of the 538 votes the largest state, California, has 56 and the smallest, Wyoming, 3. To become President the winning candidate has to secure more Electoral College votes than the nearest candidate. In 2016͛'s two-horse race the winning number was 270: Trump won 304 and Clinton 227. The popular vote, the vote cast across all states, does not matter. Winning reliably Democrat voting states like New York and California by large margins did not give Clinton the presidency. Winning Republican states and a large swing state like Florida, plus small, midsize competitive states like Michigan, Wisconsin and Ohio gave Trump the votes he needed.
The people, represented by their state, supplies the president, but the autonomous federal legislature, the US Congress, being elected separately to the president, checks and balances him or her and their executive. Any president, if in firm control of their executive, often has little clout with Congress. Knowing it loses more legislative battles than it wins, the presidential executive has often to fight with the Congress; more often than not the President, unable to get his or her way, has to bargain and compromise with it. For the policy agreed to be President and Congress to be enacted it has then to pass muster with a Supreme Court charged with agreeing such policy is permissible under the rights and responsibilities set out in the US constitution. The President cannot be removed when serving his or her four-year term (being able to serve only two terms in total). Only a super majority of the Congress can impeach him or her and only when he or she has committed a 'high crime or a misdemeanour', not for being unpopular or for having made political mistakes. A President can continue governing even after they have been impeached by the House of Representatives (as was the case with Donald Trump in 2019). The process then moves to the Senate, the upper chamber where a two-thirds majority of the Senate is needed to convict a President. The first time Trump was impeached, he was acquitted by the Republican-led Senate so he remained in power. However, his second impeachment trial by the now Democrat-led Senate could find Trump guilty and disqualify him from running again in the future.
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