Why is gun crime rising again in America?

Surging gun crime in the United States has put the issue of gun control back on the agenda. But why is it happening - and can anything be done? Washington correspondent Martin Wall reports. <br /><hr><p style='color:grey; font-size:0.75em;'> See <a style='color:grey;' target='_blank' rel='noopener noreferrer' href='https://acast.com/privacy'>acast.com/privacy</a> for privacy and opt-out information.</p>