The shooting carried out by an African-American man in Dallas, which cost five police officers their lives, and the deaths of two black men brutally killed by white officers rekindled racial tensions just as the Republican Party is about to officially choose Donald Trump as its presidential candidate.

Never has Martin Luther King’s dream of a united and just America seemed so far-off. At the end of a tragic week, racial tensions have once again reached a boiling point. As President Barack Obama stressed, nothing justified the “despicable” act of terror committed in Dallas, which cost five police officers their lives and wounded seven others. As reprehensible as it is, can we really be shocked that a young 25-year-old black man wanted to kill white cops?

As one recalls, two African-Americans were killed this week in Louisiana and in Minnesota, the umpteenth victims of the police violence that defies the basic principles of law enforcement. One man was killed in cold blood in his car in front of his fiancée and her four-year-old daughter, inciting protests throughout the country.

You’d have thought that the deaths of Michael Brown, Eric Garner as well as Tamir Rice would have served as lessons. Repeated police shootings have aroused very conflicted feelings within the African-American community: a profound anger, powerlessness and the feeling that African-Americans are not an integral part of American society.

The emergence of the “Black Lives Matter” movement burst out of a need for dignity from a community that rejects the status quo, that demands fair and nonviolent police practices, reform of the prison and criminal justice systems as well as support for schools in a country where, for largely socio-economic reasons, academic segregation has made a strong resurgence.

Of course, if the U.S. is racially heated to such a degree, it's because of its turbulent history, but also because of a Republican Party that hasn’t stopped exploiting racist sentiments to better secure its white electorate. By nominating Donald Trump during the convention in Cleveland — the city of the late Tamir Rice, a 12-year-old black child shot while he was playing with a fake gun in an empty park — the party will choose a presidential candidate who will preach, only more vulgarly and outrageously, what the party hasn’t ceased to practice, notably with regard to the first black president of the United States.