My criticisms of Christian fundamentalism with its slipshod attitude towards science is well-known, but as I said earlier, not a few atheists are just as bad as the fundamentalists in their reasoning, and the Jesus-mythers are arguably some of the worst. Hannam says it all here:
Did Hannibal Really Exist?
To ask whether or not the great Carthaginian general Hannibal ever actually existed might seem rather pointless. It might be an exercise for a student learning about the nature of historical evidence, but not something any serious scholar would waste time on. But maybe we should not be too hasty in acquiescing with the opinion of establishment historians (in other words, there's a plot by academics stifling debate).
In fact, although there is plenty of writing about Hannibal, none of it is contemporary and there is no archaeological evidence for him at all (not surprising given the Romans razed the city from whence he came). Furthermore he is not mentioned in any Carthaginian sources, which is incredible, given he was supposed to be their greatest leader (there are no Carthaginian sources as the Romans burnt their city down)! We find when we actually try to pin him down he tends to recede further into the mists of time. His exploits, such as leading elephants over the Alps, are clearly legendary (the skeptic pretends to be incredulous but seems happy to buy his own amazing theory) and it is not hard to find a motive for the creation of this colorful character by Roman writers (as long we can invent a motive for fabrication we can assume that fabrication exists).
Rome and Carthage were great trading rivals in the Western Mediterranean and it did not take them long to come to blows. Rome signed a peace treaty but, under the leadership of the elder Cato, desperately wanted to rid itself permanently of the competition (this is actually true and so helps to conceal the moment when we slip into fantasy). The Romans needed an excuse and the idea they developed was brilliant. Like many ancient civilizations, the Romans rewrote history as it suited them to exhibit their own prowess (a useful and exaggerated generalization). Consequently we should not be surprised to find that they invented a great enemy from Carthage to demonstrate the threat still existed and justify a further war to wipe them out.
The author of the fiction was Cato himself (we need someone to point the finger at; note also how there is no distinction made between the background material above and theorizing here), as Cato wrote the earliest Roman History (true as well, as it happens). But it was intended simply as a justification for a further war with Carthage. It contained the details of Hannibal's alleged campaigns against the Romans, including his victories on Italian soil (Cato's history has conveniently not survived so we can speculate freely about what it contained). Cato brilliantly combined the truth with his own anti-Carthaginian propaganda with the intention of goading Rome into another wholly unjustified war with the old enemy (give the fabricator lots of credit for his invention). Once the war was over and Carthage was razed to the ground, the Romans were able to ensure that only their version of history survived (this is important as it enables all other sources to be declared forgeries).
Therefore the myth of the great Carthaginian war leader became an accepted fact. Later Roman historians like the notoriously unreliable Livy (we have to denigrate counter sources) simply assumed Cato's fabrications were true (because the ancients were stupid and simply could not do any research themselves).
One hundred years from now, when religions have been built around the lives of Oprah and Elvis, there are bound to be sceptics who use this logic to show Elvis and Oprah were myths.
In history there is little that is certain, but there is also a level of skepticism that makes the task of the historian impossible. With such skepticism, we could happily reject the existence of almost anyone we like, including such influential figures as Hannibal. Furthermore, the thesis that Jesus never existed requires selective skepticism about which sources are reliable and how others are interpreted. In the end, if Jesus did not exist, the rise of Christianity is even more incredible and all but impossible to explain.