But yesterday that dream looked as if it had been defeated by an inflexible and maddening cultural phenomenon that has bedevilled travellers for centuries: Russian bureaucracy.
Seventeen thousand miles and seven-and-a-half years into his journey of a lifetime, with another 19,000 miles and four years to go, an obscure Russian court above the Arctic Circle ruled that the former paratrooper was guilty of breaking border rules and should be deported. A deflated Mr Bushby is expected to be flown to Alaska within days with a stamp in his passport saying he will not be allowed to return to Russia for at least five years.
He has vowed to appeal but, barring a surprise, it seems that his extraordinary overland journey is at an end before he has even reached the halfway point.
The divorced father has struggled through Panamian swamps, weathered snowstorms in Alaska, and evaded Colombian guerrillas but, prosaically, it looks like his failure to get his passport stamped will have been his undoing.
The 37-year-old adventurer ran into trouble after crossing the Bering Strait, the 58-mile ice bridge which links Alaska to Russia. Earlier this month, he made the perilous crossing with Dmitri Kieffer, an American citizen. Both had Russian visas, but did not enter the country through an official point of entry because of their unorthodox method of arrival and, as a result, did not get the requisite stamps in their passports. To compound Russian suspicions, Mr Bushby was carrying a GPS locator device and a Colt Magnum .44 pistol, apparently to protect himself from polar bears.
Nor had the two men warned Russian officialdom in advance that they were coming across the Bering Strait, a feat accomplished by only an elite club of Arctic explorers.
Coming three months after an embarrassing Cold War-style spy scandal surrounding the British Embassy in Moscow, the Russian authorities were quick to take a dim view of Mr Bushby's "incursion". The fact that, in Soviet times, the remote Arctic area was allegedly bristling with sensitive military hardware is likely to have further stoked suspicions.
The Cold War may have thawed but, to this day, visitors to the far eastern Chukotka province are required to get special permission from the local authorities on top of a visa to enter the area. It is not clear whether Mr Bushby had such permission.
By a bizarre twist of fate, the governor of Chukotka is none other than Roman Abramovich, the billionaire owner of Chelsea F.C. Indeed Mr Bushby's father, Keith Bushby, had hoped that the rich and powerful Russian might be able to pull a few strings to allow his son to carry on his way.
But The Independent has learnt that, even though he would like to help, Mr Abramovich feels he is powerless as the matter is strictly the preserve of the FSB security service.
"It's a federal matter," said a source close to the situation. "It's like asking Ken Livingstone to change national laws in the UK. It's just not possible."
Keith Bushby says his son's morale is low and that though it hasn't sunk in, he knows he has suffered "one hell of a setback". "He can't imagine that his expedition is finished ... because he couldn't get a stamp in his visa," he said in a phone interview from his home in Hereford.
Mr Bushby Jnr set out from the southern tip of Chile in 1998, and has already walked the length of South and North America, and somehow found time to release a book called Giant Steps about his journey. His plan was to trek across Asia and Europe, walking back through the Channel Tunnel to the UK and his home in Yorkshire in 2009.