The U.S. military conducted the first test of a ground-launched cruise missile since the United States withdrew from the landmark 1987 Intermediate-range Nuclear Forces Treaty with Russia this month.
The flight test of the missile took place Sunday afternoon from San Nicolas Island, off the coast of Los Angeles.
"The test missile exited its ground mobile launcher and accurately impacted its target after more than 500 kilometers [310 miles] of flight," the Pentagon said in a brief statement.
"Data collected and lessons learned from this test will inform the Department of Defense's development of future intermediate-range capabilities."
The missile was configured for a conventionally armed test warhead, the statement said.
Imagery provided by the Pentagon showed the missile exiting a multiple-missile launch canister and igniting.
The missile fired was a variant of the storied Tomahawk cruise missile, the mainstay of American long-range range strike capabilities, according to the Pentagon.
The missile launcher used in the test was identified by a Pentagon spokesman as the Mark 41 Vertical Launch System, a launcher used with the Aegis Ashore missile defense system.
Russia has accused the Aegis Ashore missile defense as potentially being used for offensive missiles.
The Pentagon said the system tested is different than the Aegis Ashore system deployed in Romania and planned for Poland that is purely defensive and incapable of firing a Tomahawk.
The BGM-109G ground-launched cruise missile was deployed from 1983 to 1991 and all of the weapons were destroyed under INF. That nuclear-tipped missile had a range of 1,600 miles.
Citing Russian noncompliance, the United States withdrew from the INF Treaty on Aug. 2 ending a Cold War-era arms agreement that limited ground-launched cruise and ballistic missiles with ranges of 310 and 3,400 miles.
Russia began secret development and testing of a new ground-launched cruise missile, the SSC-8, in the early 2000s.
The treaty violation was ignored by the administration of President Barack Obama that had sought to avoid upsetting its arms control agenda with Moscow.
The treaty breach also was suppressed during debate 2010 on the New START strategic arms treaty that was ratified with Republican support.
Secretary of State Mike Pompeo announced the INF treaty withdrawal Aug. 2 noting that Moscow had refused to return to compliance with the treaty by destroying its SSC-8s.
"Russia is solely responsible for the treaty's demise," Pompeo said.
The secretary said the weapon was flight-tested since the mid-2000s and currently Russia has fielded "multiple battalions of its noncompliant missile."
Efforts to coax Russia back into compliance were first attempted in 2013 and were systematically rebuffed for six years, he noted.
Russia was notified in February that the United States regarded Moscow to be in material breach of the INF treaty and was given six months to correct the violation.
"As it has for many years, Russia chose to keep its noncompliant missile rather than going back into compliance with its treaty obligations," Pompeo said.
"The United States will not remain party to a treaty that is deliberately violated by Russia," he added.
The new illegal missile poses "a direct threat to the United States and our allies and partners," Pompeo said.
Pompeo said the United States remains committed to effective arms control.
President Trump said recently he spoke to leaders of China and Russia and wants to expand any future strategic arms agreements to include both Beijing and Moscow.
China was not a party to the INF treaty and in the years since 1987 has deployed several types of INF missiles, both conventionally armed and nuclear-tipped.
China so far has rebuffed U.S. diplomatic overtures to enter arms talks.
Russia continues to deny its SSC-8 missile violates the treaty and has accused the United States of violating the treaty by using INF range missiles as missile defense test targets. Target missiles, however, are not covered by the 1987 threat.
The INF treaty was reached during the administration of President Ronald Reagan and was a response to Moscow's deployment of SS-20 missiles in Europe and the counter-deployment of U.S. Pershing II and ground-launched cruise missiles there.
Earlier this month, Trump commented on the decision to withdraw from INF
"We have been speaking to Russia about a pact for nuclear so that they get rid of some, we get rid of some," he said. "We'd probably have to put China in there."
The United States, Russia, and China are three major nuclear powers and while China's arsenal includes lower numbers of forces "we would certainly want to include China at some point" in future arms talks.
"I've discussed it with President [Vladimir] Putin. I've also discussed it with China, and I will tell you, China was very, very excited about talking about it, and so is Russia. So I think we'll have a deal at some point."
Trump said of the INF violation that the Russians "weren't living up to their commitment."
Trump said the United States is modernizing its nuclear forces and "we have new nuclear [weapons] coming."
"I hate to tell that to people. I hate to say it because it's devastating, but we've always got to be in the lead," he said. "Hopefully—and hope to God—you never have to use it."
Trump sidestepped a reporter's question about whether testing a ground-launch cruise missile would be provocative.
"We have the finest military in the world. We make the finest equipment in the world by far, whether it's fighters, whether it's missiles, whether it's the ships, whether it's submarines," he said. "There's nobody to compete with us. But if we could hold off spending by getting a pact with Russia and with China, that would be very good for all three countries."
Mark Schneider, a former Pentagon nuclear weapons specialist, said the test was "literally the first time since the Reagan-Bush era that Russia has been made to pay any price for violating an arms control treaty in a serious way."
"The lack of any response to serious Russian arms control violations until the recent actions by President Trump is literally the greatest advantage Putin has in his confrontation with the West, not to mention Japan," Schneider said.
The fact that NATO also has declared the SSC-8 a violation shows the evidence for the breach is strong, he noted.
"Quite frankly, I would prefer the missile to be dual capable but a conventional-only system is far better than doing nothing," Schneider said.
"The early timing of this test will drive home to Putin that we are serious about compliance," he added. "President Trump deserves the highest praise for his actions on this issue."
Schneider predicted arms control advocates will criticize the test but noted that they "as usual, will be on the wrong side of this issue, i.e. colluding with Russia against U.S. national security interests."
Daryl Kimball, director of the Arms Control Association, tweeted that the recent test was a "wrong move after #INF Treaty termination."
Rick Fisher, a China military affairs expert, praised the latest intermediate-range missile test.
"We are now joining a theater missile and nuclear arms race in which China and Russia have been the only real runners," said Fisher, a senior fellow at the International Assessment and Strategy Center.
"If we don't catch up fast we create temptations for wars that could burden Americans for generations. Unlike the previous administration, this one is taking the right steps that offer the best chances of keeping our kids out of war."
The administration deserves credit for responding quickly in developing and deploying missiles urgently needed to deter China and North Korea, he said.
Fisher said it is urgent for the United States to also rapidly develop and deploy large numbers of ballistic and hypersonic missiles to deter both China and Russia,.
"In addition, as there are Russian estimates that China has over 600 tactical nuclear weapons, U.S. forces also urgently require new tactical nuclear weapons," he said.
Moscow responded to the U.S. treaty withdrawing by suspending Russia's obligations under the accord.
NATO Secretary General Jens Stoltenberg backed the U.S. withdrawal decision and said the alliance would respond in a measured way to what he termed the "significant risks" posed by the SSC-8.