Is Russian President Vladimir Putin crazy or crazy like a fox?
In remarks quoted by "The New York Times," German Chancellor Angela Merkel reportedly wondered aloud whether the Kremlin leader was "living in another world." And despite the fact that the German government later denied Merkel's comments, an increasing number of analysts have been suggesting that, with his military intervention in Ukraine, Putin may have indeed taken leave of his senses.
Stanislav Belkovsky, an influential Moscow-based political commentator, says "the poor guy's brain isn't working."
And Andrei Zubov, a professor at the prestigious Moscow State Institute of International Relations, agrees.
"We always make prognoses based on the assumption that the politician, even if selfish and cruel, is intelligent and rational. But what we see now is the behavior of a politician who has lost his mind," Zubov says.
Rumors of Putin's supposed madness have become so prevalent in recent days that one can't help but recall the "madman theory" of former U.S. President Richard Nixon, whose administration tried to plant the suspicion that he was unbalanced in order to scare geopolitical opponents into concessions.
But Putin has been such a shrewd political player for more than a decade and a half, and many observers see cold calculation and deliberation, rather than madness, in his latest Ukraine gambit.
Jan Techau, director of Carnegie Europe in Brussels, suggests that Putin is simply employing a cost-benefit calculus that is completely different from that used by Western politicians. Putin, he says, sees an existential threat to Russia in Ukraine's westward drift and therefore is willing to bear a very high political and economic cost to prevent it -- and has been preparing the ground to do so for a long time.
A U.S. diplomatic cable from the Kyiv mission in 2006 that was released by WikiLeaks accuses Russia of funding "a deliberate effort to destabilize Crimea, weaken Ukraine, and prevent Ukraine's movement west in institutions like NATO and the EU." It says that plan had been in operation at least since the Orange Revolution of 2004.
Ben Judah, the author of "Fragile Empire: How Russia Fell In And Out Of Love With Vladimir Putin," says "the crucial thing that Putin was trying to achieve in Ukraine over the past few weeks was to continue to impose a Russian veto over Ukraine's future."
"From the moment that Russia threatened a trade war to block [deposed Ukrainian President] Viktor Yanukovych signing an Association Agreement with the European Union to the decision to intervene in Crimea, it is all about this one thing -- it is that Ukraine can't fully have autonomous control over its own destiny," Judah says.
In addition to geopolitics, domestic considerations are also a strong motivator for Putin, analysts say.
Russian opposition figure Leonid Gozman said in Crimea, Putin is engaged in a "genuine attempt at an Anschluss," an apparent reference to Adolf Hitler's annexation of Austria to Nazi Germany in 1938.
But Gozman says the reason Putin is seeking outside "enemies" is to bolster his political legitimacy at home, which has declined among much of the population since vocal public opposition to him emerged in late 2011.
"What is Vladimir Putin's situation? He has serious problems with his legitimacy, which began -- or at least he recognized them -- when he was booed [at a martial arts event in Moscow's] Olympic [stadium] back before the last Duma elections," Gozman says.
"He's a smart person and he understands that his charisma is weakened. It happens -- they loved him and now they don't love him. So he needs some other foundation for his legitimacy. And another foundation for legitimacy is victory."
Likewise, analysts say the Ukrainian opposition's successful overthrow of an authoritarian government is a dangerous precedent for Putin.
Russian political columnist Yevgeny Ikhlov says Putin is acting because of the example of a democratic revolution in neighboring Ukraine "where there will be lustration, the exposure of corruption, free elections."
"Such an example would show the population of the Russian Federation how all that can be normal," Ikhlov says.
Regardless of Putin's motivations, is there anything the West can do to counter him?
Russian history professor and political commentator Valery Solovei posted on Facebook on March 3 that "well-informed" sources tell him Putin made the decision to move into Crimea personally and that he did so in part because he believes "he is opposed in the West by the weakest political elite of the entire postwar period."
Solovei adds, however, the upper echelons of the Russian political elite is deeply split by the decision and that those with economic assets in Europe are "scared to death."
Indeed, author Judah says, the ruling elite in Putin's Russia is, theoretically, extremely vulnerable to Western sanctions.
"The Russian elite is theoretically extremely vulnerable to any choice by the European Union to clamp down on its tax havens or to use visa bans or freeze bank accounts or restrict Russian companies' access to its stock exchanges or financial services. But Putin is absolutely confident the European Union is not going to do that," Judah says.
"Half the Putin cabinet has assets across Europe," Judah says. However, most European countries -- particularly Britain and Germany, "have long ceased to be interested in taking any policies toward Russia that would harm their [own] interests."
Analyst Techau agrees the West lacks the will and the unity to impose serious economic penalties on Russia, although it has the ability to do so. Both Judah and Techau say the United States has taken a harder line against Russia in general -- notably the so-called Magnitsky Act, which imposed targeted sanctions against Russian officials believed to be involved in human rights abuses -- but that Washington has limited leverage because Russian assets are overwhelmingly located in Europe.
Putin understands, Judah says, the Cold War days -- when the United States could de facto order European countries to impose various trade sanctions on the Soviet Union -- are over.
"None of this, of course, is likely to happen because the very same European elite that funds political parties, that goes to cocktail parties with European political leaders, the whole Davos elite, has made its fortune in the last decade of slow-to-nonexistent economic growth off rents from oligarchs," Judah says.
RFE/RL Russian Service correspondent Mikhail Sokolov contributed to this story from Moscow, and RFE/RL correspondent Claire Bigg contributed from Prague.