Right. The Punisher is a more adult take on Batman. Early on Batman used guns, but it was very early, and at the same time then it was more focused on fantasy, as it had vampires, etc.
Already by 1940 Batman had been "sanitized" and started going away from the grittier pulp/noir styling and was marketed to a younger crowd with Robin, actually pre-dating Batman getting his own comic. Over time we had stuff like Ace the Bat Dog, etc. till it became the over-the-top 1960s Adam West TV show.
In the MAX line, the Punisher, (or at the time just Frank Castle,) is a 'Nam vet (again). At the will of writer Ennis, Frank's old; he's been active for 30 years as the Punisher, or close to it, and he drops the goofy super-hero uniform, but (possibly) gains (almost) superpowers. In the MAX origin comic, Frank seems to make a deal with some unspecified dark power to survive a botched operation. However immediately he is found near catatonic, being the sole survivor of what seems to be vicious melee combat. So it's definitely left open to reader interpretation.
Punisher was not only an embrace of the vigilantism of the Western-genre resurgence at the time (1974), or sort of an answer to Batman, he was also one of the first true anti-heroes to hit it big. He was embraced by a public that had lived through Watergate, and was largely disgusted with government/authority.
The Punisher was also a bit of a mistake, if you will; he was designed to be a tier-2 supporting role character and his popularity caught Marvel off guard. This helps explain the thin-ness of his character and the sort of archetypal roots and personality early on.
Watched the Punisher episodes with my roommate, who was watching Daredevil. I thought the speech at the end was a little much, but overall very good. Put the Tom Jane and Ray Stevenson movies to shame.