North Korea has begun constructing a memorial for its soldiers killed fighting in Russia’s war with Ukraine, state media reported Thursday, as leader Kim Jong Un hailed a “historic peak” in ties with Moscow. The so-called Memorial Museum of Combat Feats will be built in the capital Pyongyang, where Kim and Russia’s ambassador to North Korea attended a groundbreaking ceremony, according to the Korean Central News Agency. Kim, addressing Thursday’s event, said the museum “is a sacred sanctuary dedicated to the immortality of true patriots.” North Korea, one of the world’s most insular nations, has become a key Russian ally...