It was a completely staged event he rehearsed and goaded the reporters into asking him about to deflect questions they had about ISIS in the Middle East for which he had no answers for.

Even then, he failed with his memorized explanation of what quantum computing is and got it wrong.

http://nationalpost.com/news/politics/im-really-hoping-people-ask-me-how-quantum-computing-works-trudeaus-geek-lecture-not-off-the-cuff

https://www.washingtonpost.com/posteverything/wp/2016/04/18/actually-justin-trudeau-doesnt-get-quantum-computing/?utm_term=.70c5f5aed72f

https://www.cantechletter.com/2016/04/no-justin-trudeau-doesnt-really-understand-quantum-computing/