President Volodymyr Zelenskyy's sacking of Ukraine's popular defense minister, Mykhaylo Fedorov, is not just a dramatic shakeup of his cabinet. It's sent shock waves through the country's political and military circles, and it's driven protesters into the streets.

Organizers cite Zelensky's lack of explanation for sacking Fedorov as key grievance.

President Volodymyr Zelenskyy sacked Mykhaylo Fedorov as defense minister, a dramatic shakeup of his Cabinet that sent shockwaves through Ukrainian political and military circles…