The Crimean War, why do some historians refer to it as " the first modern war"

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…up. Thanks to all these factors, the Crimean War was "a token of a profound change in the place of Europe in a wider world. It was a fumbling war, probably unnecessary, largely futile, certainly extravagant, yet rich in unintended consequences. It broke the spell of peace, and it removed the shadow of Russian power from central European affairs. It therefore cleared the way for the remodelling of Germany and Italy by means of war."