Sloviansk and the nearby city of Kramatorsk are both coveted by Russian forces, currently bogged down in nearby Bakhmut, as they push ahead with their invasion of Ukraine.Ukrainian military commanders this week rejected Russian statements that its forces now controlled 80% of the city, saying Moscow’s claims were an exaggeration.President Volodymyr Zelenskyy decried Russia as an “evil state” after a fatal attack on residences in Sloviansk. Why is Ukraine still holding on instead of seeking peace through negotiation ?