US media are widely reporting that former US President Donald Trump has won the Republican presidential primary in the state of South Carolina. Trump had been tipped to defeat rival Nikki Haley, who was once governor of the conservative state in the south-east of the USA, for their party’s nomination for the presidential election on November 5. To run for president in the US, a candidate must first win the internal party primaries. The candidates are then officially chosen at party conventions in the summer. The Republican nomination convention takes place in mid-July. Haley, who is regarded a…