The legacy of slavery: three challenges for the US

This week marks the 150th anniversary of the 13th amendment to the US constitution, which abolished slavery in all American states when it was ratified in December 1865.

But now, seven years after electing its first black president, America is once again going through a period of soul-searching – and one of the most difficult periods of racial tension in a generation. Even as it looks back on a century and a half of progress, new challenges lie ahead:

National security policy

With the man who could be its next president – Donald Trump – accused of inciting racial hatred with a call to ban all Muslims from entering the country, much is made of the psyche of some sections of American society, which is propelling his advance. The Guardian's Jason Burke says Trump's words "fit into a clear historic pattern" of western perceptions of Islam and Muslims. "History teaches us that the resultant hateful rhetoric will eventually pass but, depressingly, the timescale is decades, even centuries, rather than months," says Burke.

Tensions in education

Students at Princeton University are at the centre of protests demanding that the university dissociates itself from former US president Woodrow Wilson, due to his "racist legacy". That follows unrest at Yale, Dartmouth and other campuses following an incident at the University of Missouri, in which the president and chancellor tendered their resignations after accusations that they responded improperly to accusations of racism on their campus. "The anguished public meetings that spread from college to college through November highlighted previously undisclosed feelings of suffering and outrage among black and other minority students in the US," reports The Independent. "It is the latest twist in the unresolved story of racism in America."

Police shootings

The killings of African-American men by white police officers in recent years have raised deep questions about ingrained attitudes among America's law enforcement. In the latest incident, a video emerged three weeks ago of a white Chicago police officer shooting a black teenager 16 times in 2014. It followed several other similar incidents. "2016 will mark the first year the federal government will implement a reasonable attempt at counting the number of people who die at the hands of law enforcement throughout the US," reports The Guardian.