ABU HISHMA, Iraq, Dec. 6 — As the guerrilla war against Iraqi insurgents intensifies, American soldiers have begun wrapping entire villages in barbed wire. In selective cases, American soldiers are demolishing buildings thought to be used by Iraqi attackers. They have begun imprisoning the relatives of suspected guerrillas, in hopes of pressing the insurgents to turn themselves in. The Americans embarked on their get-tough strategy in early November, goaded by what proved to be the deadliest month yet for American forces in Iraq, with 81 soldiers killed by hostile fire. The response they chose is beginning to echo the Israeli...