John Bolton is one of the most divisive figures in American politics today.To some, he is Washington's most famous warmonger. To others, a fearless defender of US interests.From Iraq to Iran, Syria to North Korea, his decades of conservative foreign policy have influenced the position and actions of the US in conflicts worldwide.Since first serving under President Ronald Reagan's administration in the 1980s, Bolton built a career as a solid, conservative Republican politician.He was assistant secretary of state for international organisation affairs when President George HW Bush was in the White House, and was under-secretary of state for arms control and international security as well as ambassador to the UN for President George W Bush.Most recently, he was national security adviser to President Donald Trump. But their working relationship ended in acrimony and accusations after 17 months.Trump tweeted that Bolton's services were no longer needed in the White House, while Bolton insisted he had quit. His recent book - The Room Where It Happened: A White House Memoir - caused controversy as Bolton portrays a president driven only by his desire for re-election.On this interview, we go beyond this latest well-covered controversy to explore what was the truth of his policy advice and positions and whether he has any regrets.Did he really encourage the Trump administration to "take on the whole world at the same time", as President Trump stated? Or was he just misunderstood?We find out as John Bolton talks to Al Jazeera.- Subscribe to our channel: http://aje.io/AJSubscribe - Follow us on Twitter: https://twitter.com/AJEnglish - Find us on Facebook: https://www.facebook.com/aljazeera - Check our website: https://www.aljazeera.com/