Using examples taken from the text give me a summary of the main arguments in favour of slavery reparations in the United States and the anticipated cost of enacting such reparations

Slavery ended in the United States in 1865 with the end of the American Civil War and the ratification of the Thirteenth Amendment to the United States Constitution, which declared that "Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction". At that time, an estimated four million African Americans were set free.

Support for reparations
Within the political sphere, a bill demanding slavery reparations has been proposed at the national level, the "Commission to Study and Develop Reparation Proposals for African-Americans Act," which former Rep. John Conyers Jr. (D-MI) reintroduced to the United States Congress every year from 1989 until his resignation in 2017. As its name suggests, the bill recommended the creation of a commission to study the "impact of slavery on the social, political and economic life of our nation"., however there are cities and institutions which have initiated reparations in the US (see § Legislation and other actions for a list).

In 1999, African-American lawyer and activist Randall Robinson, founder of the TransAfrica advocacy organization, wrote that America's history of race riots, lynching, and institutional discrimination have "resulted in $1.4 trillion in losses for African Americans". Economist Robert Browne stated the ultimate goal of reparations should be to "restore the black community to the economic position it would have if it had not been subjected to slavery and discrimination". He estimates a fair reparation value anywhere between $1.4 to $4.7 trillion, or roughly $142,000 (equivalent to $162,000 in 2021) for every black American living today. Other estimates range from $5.7 to $14.2 and $17.1 trillion.

In 2014, American journalist Ta-Nehisi Coates published an article titled "The Case for Reparations", which discussed the continued effects of slavery and Jim Crow laws and made renewed demands for reparations. Coates refers to Rep. John Conyers Jr.'s H.R.40 Bill, pointing out that Congress's failure to pass this bill expresses a lack of willingness to right their past wrongs.

In September 2016, the United Nations' Working Group of Experts on People of African Descent encouraged Congress to pass H.R.40 to study reparations proposals. Still, the Working Group did not directly endorse any specific reparations proposal. The report noted that there exists a legacy of racial inequality in the United States, explaining that "Despite substantial changes since the end of the enforcement of Jim Crow and the fight for civil rights, ideology ensuring the domination of one group over another, continues to negatively impact the civil, political, economic, social and cultural rights of African Americans today." The report notes that a "dangerous ideology of white supremacy inhibits social cohesion among the US population".

The topic of reparations gained renewed attention in 2020 as the Black Lives Matter movement named reparations as one of their policy goals in the United States.

In 2020, rapper T.I. supported reparations that would give every African American US$1 million and asserted that slavery caused mass incarcerations, poverty, and other ills.

In spite of progressive changes since the end of enforcement of Jim Crow and the successes of the fight for civil rights there are still inherent racial inequalities in the USA which negatively affect the civil, political, economic, social and cultural rights of African Americans today.  A United Nations report of 2016 did not endorse a specific reparations proposal, but did call out that there is an ideology of white supremacy present in the population of the United States that inhibits social cohesion.  Further arguments have been made identifying slavery as a cause of mass incarcerations, poverty and other ills that affect today’s African Americans.
It could be argued that there is an inherent acknowledgement that the case exists to examine the impact of slavery on the social, political and economic life of the United States in the annual submission to Congress of the "Commission to Study and Develop Reparation Proposals for African-Americans Act”.  There are also individual cities within the USA which have instituted reparations.  Estimates of the cost to African Americans of the United States’ history of discrimination have been estimated variously at $1.4 trillion, $4.7 trillion, $5.7 trillion, $14.2 trillion and $17.1 trillion.  These estimates express the projected cost in $ to restore the black community to the economic position it would have if it had not been subjected to slavery and discrimination.