(CNN) -- How far will Russia's new President Dimitry Medvedev emerge from the shadow of Vladimir Putin, the man who will be his Prime Minister and whose path he has vowed to continue? The world, and especially Russia's neighbors in Europe, will wait anxiously to see.
Key tests will come in several areas: missile defense, Russia's relations with NATO and the EU, energy security and Kosovo. And one important early indication of how much Medvedev will take charge of international relations, constitutionally the responsibility of the president, will be whether he or Putin attends this year's G8 meeting in Japan -- or whether both will go.
Putin has left no doubt over recent years about Russia's anger at the eastward expansion into former Soviet bloc countries of the European Union and NATO, and the willingness of those two organizations to seek a role in countries like Ukraine, Georgia and Belarus. Russia still regards them as within its sphere of influence.
Putin's mission has been to restore Russia's role as a world power after what he sees as the humiliations of the 1990s. He has been massively aided in that mission by Russia's transformation from an economic basket case to an oil and gas-rich economic predator, on which EU countries will soon depend for more than 40 per cent of their energy supplies.
Following the knock-on effects of cutting off gas supplies to Ukraine in January 2006, European leaders will be watching for an early clue as to whether Medvedev too will be prepared to use energy as a political weapon.
They do not forget that as well as being first deputy prime minister he has also been chairman of Gazprom, the state monopoly energy giant.
There is no doubt already where Medvedev stands on Kosovo. In the latter stages of what passed for his election campaign he visited Belgrade both to sign a deal for Gazprom and to demonstrate his and Russia's solidarity with the Serbs in their fervent and continuing opposition to Kosovo's declaration of independence.
On missile defense, the West may be too ready to dismiss Russia's objections as political posturing, while those in the Kremlin harbor real fears that a US defense shield with installations in Poland and the Czech Republic could be turned to offensive purpose.
We have heard little on the subject so far from Medvedev. The test will be whether he too adopts the 'Cold War' and 'arms race' rhetoric of Putin and repeats his threats to target missiles on European countries participating in the missile defense program.
There we are unlikely to see any lessening of tension. Putin has accepted an invitation to attend the NATO summit in the first week in April at which some will be pressing for Ukraine and Georgia to be issued with invitations to start on the path towards membership.
Against all those worries, European diplomats have fastened on to some hopeful signs that Medvedev might be a touch more relaxed in his relations with the West -- signs which go beyond his disclosure that in younger days he was a fan of Led Zeppelin and Pink Floyd.
Firstly, they note that Medvedev, a lawyer who has proved himself as a bureaucrat but not really yet as a performer on the political stage, has no links either with the military or with the security services. His instincts appear to be more liberal than those of his mentor.
He told the World Economic Forum in Davos last year, for example, that "we are fully aware that no undemocratic country has ever become truly prosperous." In a campaign speech in Siberia he insisted: "Freedom is better than lack of freedom --- this principle should be at the core of our politics. I mean freedom in all its manifestations:-personal freedom, economic freedom and finally freedom of expression."
Pessimists dismiss that as lip service, optimists hope that Mr Putin has boosted his technocrat protégé not just to keep pulling the strings in the Kremlin but in the knowledge that change is needed and that Medvedev can be trusted to conduct that process without creating upheaval.
EU leaders, who have been starkly critical of the quality of democracy in Russia, will be looking for some practical follow-up to Medvedev's words. But they too have to be careful about their tactics. Most of them regard his election as little more than the public rubber-stamping of a selection process conducted by Putin. But if they say so too directly they risk alienating a man with whom they will need to do business over the next eight years. E-mail to a friend