U.S. Defense Secretary Ash Carter accused Russia of endangering world order, citing its incursions in Ukraine and loose talk about nuclear weapons, and said the U.S. defense establishment is searching for creative ways to deter Russian aggression and protect U.S. allies.
In remarks Saturday at the Ronald Reagan Presidential Library after eight days of travel in Asia, Carter also expressed concern about China's expanding influence and growing military might. But he reserved his stronger words for Russia.
Carter said Russia is undertaking "challenging activities" at sea, in the air, in space and in cyberspace.
"Most disturbing, Moscow's nuclear saber-rattling raises questions about Russian leaders' commitment to strategic stability, their respect for norms against the use of nuclear weapons, and whether they respect the profound caution nuclear-age leaders showed with regard to the brandishing of nuclear weapons," he said.
His remarks were perhaps the strongest he has expressed about America's former Cold War foe.
"We do not seek a cold, let alone a hot, war with Russia," he said. "We do not seek to make Russia an enemy. But make no mistake; the United States will defend our interests, our allies, the principled international order, and the positive future it affords us all."
The backdrop to Carter's remarks is the reality that after more than two decades of dominating great-power relations, the United States is seeing Russia reassert itself and China expand its military influence beyond its own shores.
Russian passenger plane crashes in Egypt
Russian passenger plane crashes in Egypt
Egyptian soldiers collect personal belongings of plane crash victims at the crash site of a passenger plane bound for St. Petersburg in Russia that crashed in Hassana, Egypt's Sinai Peninsula
In this Russian Emergency Situations Ministry photo, made available on Monday, Nov. 2, 2015, showing Metrojet Airbus A321-200 flight 7K9268 flight recorder on display at an undisclosed location in Egypt
Mourners lay flowers at Pulkovo International Airport outside St. Petersburg. Russia on 1 November mourned its biggest ever air disaster after a passenger jet full of Russian tourists crashed in Egypt's Sinai, killing all 224 people on board. Flags were at half mast on the parliament building, in the Kremlin, and on other official buildings in honour of the victims, most of whom were from Russia's second-largest city of Saint Petersburg
People pay their respects at the entrance of Pulkovo airport outside St. Petersburg, during a day of national mourning for the plane crash victims
Debris from the plane crash in Egypt
A piece of an engine of Russian MetroJet Airbus A321 at the site of the crash in Sinai,
8/20 The crash site debris
Flight 7K9268 crashed in the Sinai peninsula, in all probability killing every one of the 224 people on board
9/20 The crash site debris
Debris lies strewn across the sand at the crash site
10/20 Relatives in St Petersburg
Relatives react after a Russian airliner with 217 passengers and seven crew aboard crashed, as people gather at the Kogalymaviaís information desk at Pulkovo airport in St Petersburg on 31 October
11/20 Relatives in St Petersburg
A relative of a passenger of MetroJet Airbus A321 at Pulkovo II international airport in St Petersburg, Russia, 31 October 2015.
12/20 The plane's journey
The plane's last recorded radar position above the northern Sinai peninsula
13/20 Where it crashed
A satellite view from Google Maps of the rough area where the plane crashed, in the mountainous Hassana region of the Sinai peninsula.
14/20 The plane
The Metrojet's Airbus A-321 with registration number EI-ETJ that crashed in Egypt's Sinai peninsula
REUTERS/Kim Philipp Piskol
15/20 The plane
The crashed Airbus A321 at Domodedovo international airport, outside Moscow,, on 20 October
16/20 Relatives at in St Petersburg
A relative of a passenger on MetroJet Airbus A321 at Pulkovo II international airport in St Petersburg
17/20 Relatives at in St Petersburg
Relatives of passengers of MetroJet Airbus A321 at the Crown Plaza hotel in St Petersburg
18/20 Bodies being repatriated
An Egyptian soldier prays as emergency workers prepare to unload bodies of victims from a police helicopter to ambulances at Kabrit military airport on 31 October.
19/20 Bodies being repatriated
Ambulances line up as emergency workers unload bodies at Kabrit military airport, 20 miles north of Suez, on Saturday
20/20 Bodies being repatriated
Egyptian paramedics load the corpses of victims into a military plane at Kabrit military air base by the Suez Canal on October 31, 2015
Carter cited several pillars of the international order that he argued should be defended and strengthened: peaceful resolution of disputes, freedom from coercion, respect for state sovereignty and freedom of navigation.
"Of course, neither Russia nor China can overturn that order," he said. "But both present different challenges for it."
Russia under President Vladimir Putin is challenging the U.S. in many arenas, including the Arctic, where last year Moscow said it was reopening 10 former Soviet-era military bases along the Arctic seaboard that were closed after the Cold War ended in 1991. Russia also is flying more long-range air patrols off U.S. shores.
Carter left open the possibility that Russia's role in Syria could evolve into one the U.S. can embrace.
"It is possible - we'll see - Russia may play a constructive role in resolving the civil war," he said.
In a question-and-answer session with his audience, Carter said he believes Putin "hasn't thought through very thoroughly" his objectives in Syria. He called the Russian approach there "way off track."
As Russia makes what Carter characterized as threatening statements about its potential use of nuclear weapons, the U.S. is modernizing its entire nuclear arsenal — not only the submarines, bomber aircraft and land-based missiles that are armed with long-range nuclear weapons, but also the weapons themselves.
"We're investing in the technologies that are most relevant to Russia's provocations, such as new unmanned systems, a new long-range bomber, and innovation in technologies like the electromagnetic railgun, lasers and new systems for electronic warfare, space and cyberspace, including a few surprising ones I really can't describe here," he said.
Carter said China is the single most influential player in Asia's future, and he noted that earlier this week he went aboard an American aircraft carrier in the South China Sea to demonstrate U.S. commitment to freedom of navigation. The U.S. objects to China's claims of territorial limits around disputed artificial islands there.
"As a rising power, it's to be expected that China will have growing ambitions and a modernizing military," he said. "But how China behaves will be the true test of its commitment to peace and security."
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