North Korea has warned the U.S. its prepared to engage in a total conflict if the Pentagon missteps during joint military drills with South Korea.Citing a commentary released Thursday by state-run newspaper Rodong Sinmun, the official Korean Central News Agency (KCNA) said that the countrys recent successful intercontinental ballistic missile (ICBM) tests meant that it was capable of deterring any US plans to overthrow the government of Kim Jong Un.