Russian President Vladimir Putin continues to channel his inner Vlad the Impaler. Before the possibility of an end to the conflict in the Ukraine was raised on Wednesday,he had launched a second front in his shadow invasion of Ukraine and reportedly told European Commission President Jose Manuel Barroso that he could "take Kiev in two weeks" if he wanted to.

In response to what appears to be an increasingly rabid Russian bear, President Barack Obama paid a visit to what might at first glance appear to be one of the most unlikely places to stand up to this threat: the little Baltic nation of Estonia.

On his way to attend a NATO summit in Wales on Thursday, where the alliance will meet to discuss its future, Obama arrived late Tuesday morning in the Estonian capital of Tallinn, where he is meeting with the leaders of the three Baltic countries: Lithuania, Latvia, and Estonia. The Baltic states are the only former Soviet Union republics that are now members of both the European Union and NATO — the trans-Atlantic intergovernmental alliance formed at the beginning of the Cold War to ensure European security and, in the words of its first Secretary General, "keep the Russians out, the Americans in, and the Germans down."

But why is President Obama beginning his trip in a country with a population similar to that of Tijuana?

Estonia and its Baltic neighbors have a deep fear of Russian aggression, owing both to their history under the Soviet hammer and sickle and because of Russian threats made against them since. It's widely believed that in 2007, for example, the Russian government orchestrated a cyber attack against Estonian state websites in response to the planned removal of a Soviet war memorial.

Equally important, the successful post-Soviet development of the Baltics represents something that Putin despises: free societies within his imagined "sphere of influence" doing well without Russian dependence.

Estonia, in particular, has set up its own version of a Baltic Silicon Valley, garnering the nickname "E-stonia." The Estonian private sector has produced successful international companies like Skype and an explosion of startups. Estonian President Toomas Hendrik Ilves is one of the most tech-savvy and tweet-happy leaders in the world. Since Russia began its recent intervention in Ukrainian affairs, he's been particularly active in responding to its aggression. (His blunt style is no accident; he grew up in New Jersey.)

Meanwhile, the history of the Soviet era continues to be a source of tension between Russia and the Baltics.

The region first fell into the Soviet grip as a result of the Nazi-Soviet pact of August 1939, when Hitler and Stalin secretly agreed to divide Eastern Europe, giving these states to the Soviet Union. Hitler, of course, later reneged on the agreement and occupied these countries when he invaded the Soviet Union, before the Soviets swept back into the Baltics in 1944.

The dissolution of the Soviet Union also began in the Baltics.The three republics began protesting for their own independence well before the Berlin Wall fell in November 1989. Their independence movements served as a precursor to the collapse of the entire Soviet Union in December 1991.

While it's unlikely that Putin would directly invade the Baltics — doing so would effectively trigger a war between the US, Europe, and Russia, as the Baltic countries would invoke Article 5 of the NATO Treaty, which calls for collective self-defense — Obama's visit offers a chance to visibly demonstrate American support for the region and its resolve to Russian, an impression that will be further bolstered when he attends the NATO summit in Wales.

With 60 world leaders in attendance along with six NATO warships docked in Cardiff Bay, the summit is designed to show the strength and international reach of the 28-member alliance. But it will also have to manage differences within the alliance as it contends with an ever-growing litany of international crises.

"Chief among these challenges is finding a unanimous response to Russia's aggression against Ukraine," Patrick Keller, an international security expert with the Konrad Adenauer Foundation, told VICE News. "While some allies call for sending a stronger message of deterrence to Putin, others — especially in Europe's west and south — worry about alienating Russia even further and locking NATO into an unnecessary replay of the Cold War. Mr. Obama's trip to Estonia is a crucial piece of the puzzle, because the president's visit will reassure his Baltic allies. The visit will not deliver the permanent presence of US troops on their soil that they are hoping for, but it might help reconcile them with the new proposal for a NATO rapid-reaction force."

The proposal for a rapid-reaction force that could be swiftly deployed within Eastern Europe would allow NATO to maneuver around its 1997 cooperation agreement with Russia, in which NATO pledged that it wouldn't build permanent bases as part of its expansion in Europe.

Further dialing up its response to Russian aggression, the US and its allies are planning to conduct training exercises in western Ukraine later this month.

But various other issues could impact the alliance in the long-term beyond the Russian threat — from the rise of the Islamic State in Iraq and Syria to the military drawdown in Afghanistan to China's military ambitions.

Chief among the disputes within NATO is the issue of "burden-sharing." The United States remains the dominant military power within the alliance. Europe's military capacity has dwindled as defense spending has fallen in recent years, particularly after the 2008 economic crisis. Apart from the US, last year only three of NATO's 28 members reached the alliance's defense-spending target of 2 percent of GDP: Britain, Greece, and Estonia.

Former US Defense Secretary Robert Gates outlined these concerns in a 2011 speech at NATO headquarters in Brussels, in which he said, "The blunt reality is that there will be dwindling appetite and patience in the US Congress — and in the American body politic writ large — to expend increasingly precious funds on behalf of nations that are apparently unwilling to devote the necessary resources or make the necessary changes to be serious and capable partners in their own defense."

A former high-ranking Pentagon official who served with NATO also emphasized to VICE News on condition of anonymity that the alliance faces internal divergence beyond the issue of burden-sharing.

"This is probably the most important summit since the end of the Cold War," he said noting the serious strategic issues that need to be resolved from within. "The alliance is in the midst of political turmoil, as nations cannot agree on the priority of the threats or a political strategy for dealing with Russia. Moreover, some nations such as Hungary — stalwarts of the post-Cold War expansion — have been taking moves away from Western liberal values. The inability to maintain a sense of shared values and strategy is a real threat to NATO. While it won't break the alliance, it could make it more difficult to get the political decisions required for joint action."

Keller, for his part, emphasized the importance of NATO's worldwide commitments.

"As important as it is to curb Russia's appetite for foreign territory, the broader strategic challenge for NATO is even more difficult," he said. "This NATO summit will help decide the future of the alliance. Should territorial defense in Europe return to be the prime — and, given the constraints of tight budgets and feeble political will, probably only — priority? Or do NATO members still accept the realities of a globalized security policy that on occasion requires military crisis management outside of Europe, be it in North Africa, South Asia, or anywhere else in the world? With the impending end of NATO's role in Afghanistan and Russia's increasing aggression, the first option has significant allure. But it would mean a shrinking of NATO's strategic horizon that in the end will jeopardize the security of all allies, especially in Europe."

The summit may demonstrate the strategic irony that Putin's actions might provide the catalyst to revitalize an alliance that remains critical to global security — if only leaders on both sides of the Atlantic can demonstrate the shared resolve to do so.