Just how much of a social and political reformer is Hu Jintao? To what extent will he defend economic reform, and how far can he be pushed on Taiwan? All these questions and more nag US officials as the Vice-President embarks on his first major mission to America. Internal intelligence dossiers do little to flesh out his biography as the 59-year-old prepares to succeed Jiang Zemin as president and Communist Party general secretary. Mr Hu will walk through the White House doors a mystery to US leaders. 'We've got the basics down and that is about it,' one US intelligence official admitted. 'We are just starting to learn about Hu Jintao the leader . . . Communist Party secrecy still reigns supreme and the big questions are all guesswork at this stage.' Getting to know Mr Hu is the single biggest US priority as he heads to the West, a task US President George W. Bush will pursue with personal relish. The pair's first meeting in February when Mr Hu introduced Mr Bush to Tsinghua University only added to the intrigue. Mr Hu was at his enigmatic best and displayed little emotion during Mr Bush's speech, and the pair only had the chance for small talk. This time around Mr Bush will be wanting to gain a sense of Mr Hu's vision for the future, according to John Tkacik, a scholar at the Heritage Foundation, a Washington think-tank with close ties to the Bush administration. 'Hu didn't get this far without being extremely cautious, so he's not about to open up just now,' Mr Tkacik said. 'Even once he is fully in power he will still have the older leaders hanging around to start with. But it would be great if we can get a sense of some of his ideas for the future of the party and so on. It is quite clear he is aware of the great challenges ahead.' A new study published at the weekend by Mr Tkacik portrays a solid party man who is by turns ambitious yet highly capable; thoughtful yet tough. Mr Tkacik notes Mr Hu attracted the favour of late paramount leader Deng Xiaoping shortly after being despatched to Tibet as local party secretary in late 1988. As civil tensions in Lhasa worsened, Mr Hu ignored instructions from then party chief Zhao Ziyang and called out the PLA to suppress demonstrations, leading to the deaths of civilians. And even as Mr Hu has more recently sought to modernise the direction of the Central Party School towards a more responsive government, democracy and 'evolutionary socialism', he has remained sharply critical of US hegemony in internal speeches. 'It is hard to explain away Hu Jintao's sentiments as anything less than reflective of a general anti-American paranoia that persists in Beijing's leadership to this day,' Mr Tkacik says in his study. Fellow Heritage Foundation analyst Larry Wortzel said despite his reformist ideas, Mr Hu was no 'Chinese Gorbachev' who would risk the security of party rule with hasty change. This meant the US had to impress upon Mr Hu that it would support him through the difficulties of WTO reforms. 'It is fair to say that in the face of great unrest, the collective weight of Mr Hu's Communist Party roots would kick in,' Mr Wortzel said. 'He would do what he had to do.' Mr Bush may not be put off, however, in the quest for a closer relationship with China via Mr Hu. His approach to Russian President Vladimir Putin, a former KGB officer with a tough record on internal security, suggests considerable pragmatism. Mr Bush repeatedly speaks of his trust in Mr Putin, describing him as a 'good man' - phrases which have sparked criticism from Mr Bush's own Republicans.