This isn't intended to scare you. But with Vladimir Putin making clear threats towards potential nuclear warfare, it's certainly a question worth asking. And a question that not very many people have considered for decades now. So, what's the status of our nuclear defenses? How do they work? And what would it take to be ready for a worst-case scenario?GUEST: Dr. James Fergusson, Deputy Director, Centre for Defence and Security Studies; Professor of Political Studies at the University of Manitoba.