'One is the smiling actor and the other is that of the Scientologist.'

The latest controversy was sparked by Cruise's appearance at a Scientology ceremony a few years ago that was only made public recently via the internet.

Respected German historian and documentary filmmaker Guido Knopp said last month that it reminded him of an infamous speech by Nazi propaganda minister Goebbels in 1943, when he asked Germans if they were ready for 'total war' and prepared to make sacrifices for victory.

'It might be that Cruise's manner of speaking is typical of many revivalist movements in the US,' Knopp told the Bild am Sonntag newspaper.

'However, the scene where he asks the Scientologists if they should cleanse the world and they all cry 'yes' has to remind any German interested in history of Goebbels' notorious Sport Palace speech.'

Though there are undeniable parallels between Cruise's appearance on stage to accept the Church of Scientology's Freedom Medal award and that of the Nazi leader more than 60 years ago, those who haven't spent their careers sifting extensively through Third Reich history like Knopp might feel it's tenuous at best to link the Hollywood star with a war criminal.

Scientology's numerous critics in Germany, however, have seized upon Cruise's somewhat creepy performance - which includes him saluting a massive onstage portrait of Hubbard - to renew their claim that the group is using the actor's popularity as a Trojan horse to infiltrate the country.

'Cruise is a victim like the rest of them, but you can't separate the actor from the Scientologist,' Ms Caberta says.

'The group has the task of using his name and reputation to improve Scientology's image.'

A recently published biography of Cruise by British author Andrew Morton claims the US actor is secretly second in command at the Church of Scientology after the organisation's top leader David Miscavige.

Morton and some commentators in Germany have even theorised that Cruise purposely took on the role of portraying Colonel von Stauffenberg, who has become a symbol of German resistance to Hitler, to help Scientology increase its foothold in Germany.

'Germany is an attractive market for them, with 82 million potential customers, a rich country,' Morton told the website of the German newspaper Die Welt last Sunday. 'The film thing was part of their strategy: Scientology announces expansion plans in Germany and their leading Scientologist Cruise gets this role.'

Germany remains a difficult place for Scientology's estimated 6,000 local adherents to operate. Their faith is officially considered based on undemocratic ideology and contrary to the German constitution.

Because of this, the organisation has long been subject to surveillance by Germany's domestic intelligence service just like neo-Nazi political parties and militant Islamist groups are. Stymied for years by Germany's refusal to give the organisation official religious status or tax exemptions, Scientology opened a new flagship centre, or church as it's known by Scientologists, in Berlin last year to raise the faith's profile.

'Since we moved into the new location in Berlin, we've had more attention - 15,000 people have visited,' says Sabine Weber, the head of the local Scientology church. 'And once the wall of resistance started to crumble, the campaign of disinformation was stepped up and the attacks started to become more and more peculiar.'

In Ms Weber's opinion, that includes an attempt to smear Cruise now with the comparison to Goebbels. 'I have to be honest with you - I find it completely irresponsible.

'Nobody overseas would dare to make such a comparison with warmongers and murderers,' she says.

But a heated national debate about Cruise's association with Scientology also flared last summer during the filming of Valkyrie, which is due for release this year.

Cruise, who looks remarkably similar to the young Colonel von Stauffenberg, was not considered by many here as the appropriate person to play the role of an aristocratic German resistance hero, who died fighting against Hitler's tyranny.

Colonel von Stauffenberg's son, Berthold Schenk Graf von Stauffenberg, said he didn't like the fact that an 'avowed Scientologist' such as Cruise was portraying his father.

The German Defence Ministry at first even appeared set to deny Valkyrie director Bryan Singer permission to film at the location in Berlin where Colonel von Stauffenberg and his fellow plotters were executed by the Nazis after the bomb planted on July 20, 1944, in Hitler's Wolfschanze headquarters in East Prussia failed to kill him.

But shooting the movie at even sensitive locations was eventually allowed after Cruise and the filmmakers received prominent backing from Oscar-winning director Florian Henckel von Donnersmarck and Frank Schirrmacher, the publisher of the influential conservative newspaper Frankfurter Allgemeine Zeitung. Both argued that having a world-famous star like Cruise portray a symbolic figure of German resistance against Hitler would do more to improve Germany's image abroad than Scientology's image in the country.

'When he plays Stauffenberg, it's an event. But he is not spreading any sect propaganda in connection with the film Valkyrie,' Mr Schirrmacher told German newsmagazine Der Spiegel last week.

'It's inappropriate to judge his performance as an actor based on his religious preferences.'

But such public displays of support for Cruise's film project are unlikely to make Germany a less antagonistic place for Scientology and those seen furthering its agenda. Mr Schirrmacher has since been subject to scathing criticism in German intellectual circles despite his open repudiation of Scientology's more questionable practices.

Scientology expert Ms Caberta believes Germany's hard-line position should be taken even further to encompass a total ban to contain an organisation that is accused of bilking their members for cash and controlling most aspects of their lives. But pushing through a ban of Scientology could be an extremely difficult process, considering the German government failed to outlaw the arguably far more dangerous neo-Nazi National Democratic Party in 2003.

And Ms Weber confidently dismisses talk of any potential ban. 'There's no basis for it - so long as German Scientologists adhere to the constitution and follow the law, then they should be treated like any other religious group,' she says.