Like you, I've never heard of him, but I'd like to see for myself what he actually did say, as there's no quoting from his interview, but just a claim that he compared the separation barrier to the walls around the Warsaw Ghetto...
I think when it comes to offense, comparisons to the Warsaw Ghetto are on a par with comparing boycotting Israeli companies because if Israel's policies towards the Palestinians to the Nazi boycott of Jewish businesses in 1933.
'In March 1933 the Nazis finally achieved a majority in the German parliament and Hitler became Chancellor. Following the victory there was widespread violence and hooliganism directed at Jewish businesses and individuals.<1> Jewish lawyers and judges were physically prevented from reaching the courts. In some cases the SA created improvised concentration camps for prominent Jewish anti-Nazis.<3>
There was widespread international horror at the persecution of the Jews. At the same time, a long-term Jewish boycott of German goods started in March 1933, prompting the UK newspaper Daily Express to go so far as to put as headline "Judea Declares War on Germany".<4>. The Nazis used this to justify a one day national boycott against Jewish Germans.<3> On 1 April 1933, the Nazis carried out their first nationwide, planned action against Jews: a boycott targeting Jewish businesses and professionals.
On the day of the boycott, the SA stood menacingly in front of Jewish-owned department stores and retail establishments, and the offices of professionals such as doctors and lawyers. The Star of David was painted in yellow and black across thousands of doors and windows, with accompanying antisemitic slogans. Signs were posted saying "Don't Buy from Jews", "The Jews Are Our Misfortune." and "Go to Palestine". Throughout Germany, rare acts of violence against individual Jews and Jewish property occurred.
The boycott was ignored by many individual Germans who continued to shop in Jewish-owned stores during the day.<5><6>'
http://en.wikipedia.org/wiki/Nazi_boycott_of_Jewish_businessesComparisons to the Nazis and the Holocaust are generally seen as minimising the horror of what the Nazis did, whether that's the intention of the person doing the comparison or not. I think the reason some people are prone to doing it is because of a mixture of ignorance of what actually did happen back then and being so wrapped up in their cause that all they focus on is trying to get across how horrible they think something happening now is by comparing it to the worst thing they can think of. And then there's obviously some who aren't ignorant of what the Nazis did, but who want to shut up people who disagree with their views, and what better way to do it than comparing those they disagree with to Nazis.