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(L/R): Head of Dutch Military Intelligence and Security Service Onno Eichelsheim, Minister of Defence Ank Bijleveld and British ambassador Peter Wilson attend a press conference of the Dutch Military Intelligence and Security Service (MIVD) at The Hague, The Netherlands, on October 4, 2018. - Dutch intelligence thwarted a Russian cyber attack targeting the global chemical weapons watchdog in April and expelled four Russian agents, the government said. The Russians set up a car full of electronic equipment in the car park of a hotel next to the Organisation for the Prohibition for Chemical Weapons in The Hague in a bid to hack its computer system, it said. (Photo by Bart Maat / ANP / AFP) / Netherlands OUT (Photo credit should read BART MAAT/AFP/Getty Images)
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Story highlights

A bigger fear than war is the possibility of accidental confrontations when you have powerful military forces lined up so close to each other.

U.S. officials and observers point to the uprising in Ukraine as the start of the uptick in Moscow's confrontational behavior.

Washington CNN —  

The war of words between America and Russia is escalating. So, too, is the movement of implements of war – from U.S. fighter jets to Russian nuclear weapons.

So is an actual war imminent?

No one in Russia, NATO or the United States has gone that far yet. Still, the rhetoric and actions from both sides have definitely ratcheted up in recent days, raising concerns of a new arms race – if not worse – amid tensions both sides blame on each other.

The major players all claim their movements are defensive and necessary responses to their foe’s provocation. None has talked of an invasion.

READ: Air Force may send F-22s to Europe over Russia ‘threat’

Still, that’s not what some experts are worried about. They say a bigger fear is what things can happen, accidentally, when you have increasingly powerful military forces lined up so close to each other.

Part of it has to do with the unpredictable nature of other actors, like Russian-backed separatists in eastern Ukraine who may broaden their own conflicts by inadvertently or purposefully striking others. The biggest such example may be the 2014 shooting down of a Malaysia Airlines commercial plane over Ukraine by rebels.

Then there’s the danger that something goes wrong as powerful militaries become more aggressive, as when a Russian fighter jet recently came within 10 feet of a U.S. Air Force reconnaissance aircraft over the Black Sea.

“Given the tempo of Russian military operations over the last year,” said Steven Pifer of the Washington-based Brookings Institution think tank and a former U.S. ambassador to Ukraine, “you have more interactions, more possibilities for things to go wrong.”

Military tit for tat

There’s no doubt that the military tit-for-tat has picked up this week.

The U.S. Navy is among those participating in a NATO landing exercise in Sweden. Around the same time, U.S. Secretary of the Air Force Deborah James announced that it could be sending some of its most advanced warplanes to Europe in a show of force.

Already, the Pentagon has rotated B-2 and B-52 bombers, F-15Cs and A-10 attack planes