If President Vladimir V. Putin is looking for international support and approval for his invasion of Ukraine, he can turn to the Chinese internet. Its users have called him “Putin the Great,” “the best legacy of the former Soviet Union” and “the greatest strategist of this century.” They have chastised Russians who protested against the war, saying they had been brainwashed by the United States. Mr. Putin’s speech on Thursday, which essentially portrayed the conflict as one waged against the West, won loud cheers on Chinese social media. Many people said they were moved to tears. “If I were Russian,...