Police in Melbourne, Australia, have arrested five Muslims—four Australian-born Lebanese, and one Egyptian-born, all legal immigrants—for planning a series of massive attacks in the city on Christmas Day. The plan—described as the “most substantial plot” in Australian history—included targeting several well-known sites in the city to cause death and destruction on December 25. Police in Victoria were involved in joint counterterrorism raids in Melbourne’s north-west where five search warrants were executed as part of “Operation Kastelholm,” which also involved the Australian Federal Police (AFP) and the Australian Security Intelligence Organisation (ASIO). In total, seven nonwhites were arrested, and police say that a core group of four—the Lebanese—intended to carry out an attack in Melbourne’s…