It's not just Andy Burnham who's been purging politicians from government. There's a wartime power struggle in Ukraine, where Volodymyr Zelenskyy ousted his top army commander Oleksandr Syrskyi – before trying to bring the country's former defence minister Mykhailo Fedorov back into government, just days after dismissing him. The sacking of Fedorov led to almost a week of nationwide unrest and represents one of the biggest political crises since Russia's full-scale invasion in 2022. So, what does all this mean for Ukraine's ongoing struggle for survival? Niall Paterson is joined by Sky's military analyst Professor Michael Clarke. Have you got a question for Niall? Email us: why@sky.uk #politics #ukraine #zelensky Follow This is Why, available for free here: https://podfollow.com/thisiswhy Follow Niall on Instagram: https://www.instagram.com/skynewsniall Follow Niall on X: https://twitter.com/skynewsniall Find out how to subscribe to our members club, Sky News Insider: https://skynews.supportingcast.fm/ Sky News Insider requires a paid subscription and is available to UK listeners aged 18 and over. SUBSCRIBE to our YouTube channel for more videos: http://www.youtube.com/skynews Follow us on Twitter: https://twitter.com/skynews Like us on Facebook: https://www.facebook.com/skynews Follow us on Instagram: https://www.instagram.com/skynews Follow us on TikTok: https://www.tiktok.com/@skynews For more content go to http://news.sky.com and download our apps: Apple https://itunes.apple.com/gb/app/sky-news/id316391924?mt=8 Android https://play.google.com/store/apps/details?id=com.bskyb.skynews.android&hl=en_GB To enquire about licensing Sky News content, you can find more information here: https://news.sky.com/info/library-sales