It is not hard to imagine that in the coming month Trump will attack ISIS (he has tasked the pentagon with giving him such a battle plan in the next four weeks), thus focusing world attention of fighting terrorist; thus leaving Putin free to continue to undermine Ukraine. And should Ukraine revert to a Russian puppet, this would place Russian tanks within 450 km of Vienna (straight through Slovakia, see attached image).
The first linked article is entitled: "Donald Trump and Vladimir Putin pledge cooperation to 'tackle terrorism'".
http://www.abc.net.au/news/2017-01-29/donald-trump-and-vladimir-putin-talk-terrorism-relations/8220866Extract: "Russian President Vladimir Putin and US President Donald Trump have said they want their nations to cooperate to defeat terrorists, including the Islamic State group.
…
Earlier in January Mr Trump suggested that NATO was "obsolete" and that the US might not come to the aid of countries that do not meet targets for their own defence spending.
Mr Trump and Ms Merkel spoke about issues including the Middle East, North Africa, their ties to Russia and the conflict in eastern Ukraine, a German Government spokesperson said, in a statement approved by both countries.
The spokesperson said Ms Merkel and Mr Trump agreed to expand their cooperation in combating terrorism and militancy."
The second linked article is entitled: "While Trump Fiddles, Putin Steps Up the War in Ukraine".
http://www.newsweek.com/while-trump-fiddles-putin-steps-war-ukraine-550603Extract: "The conflict has killed more than 10,000 Ukrainians, and displaced about 1.7 million people, according to estimates by the U.N. and other humanitarian aid groups.
The conflict—Europe’s only ongoing land war—retains the potential to escalate into a major, larger conflagration.
…
Ukrainian officials take seriously the possibility of a full-scale Russian invasion. Ukraine’s military doctrine identifies Russia as the country’s top military threat, and Poroshenko, Ukraine’s president, has ordered a top-to-bottom overhaul of the military by 2020.
There are also worries about the war spilling over to other countries throughout the region.
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The U.S. and NATO have shifted military assets eastward in a move to reassure NATO’s eastern flank, which has been rattled by Russia’s aggression in Ukraine, as well as to deter Moscow from military adventurism—covert or overt—against any NATO member.
The situation throughout Eastern Europe, especially within the former boundaries of the Soviet Union, has become a dangerous cycle of brinkmanship, with NATO and Russia locked in a tit-for-tat ratcheting up of their military presence throughout the region."
Edit, see also the Jan 28th linked article entitled: "Trump gives Pentagon 30 days to develop strategy to defeat ISIS in Iraq & Syria
https://www.rt.com/usa/375434-trump-isis-defeat-strategy/Extract: President Donald Trump has signed an executive order directing the US military to develop a preliminary plan to defeat Islamic State in both Iraq and Syria. He discussed the issue earlier in a telephone conversation with Russian President Vladimir Putin.
“It is the policy of the United States that ISIS be defeated,” reads the order published on the White House website on Saturday. “Within 30 days, a preliminary draft of the Plan to defeat ISIS shall be submitted to the President by the Secretary of Defense.”"
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Putin emphasized that “for over two centuries Russia has supported the United States, was its ally during the two world wars, and now sees the United States as a major partner in fighting international terrorism.”"