Donny Cates and Dylan Burnett have created something of an anomaly in comic book hypotheticals, seeing as how, from all accounts (at least, according to Cates), the miniseries Cosmic Ghost Rider takes place in the primary Marvel continuity (Earth-616), which we suppose technically strips away any notion of “what if” and supplants it with “what is”… well, sort of (all this time-travel business will melt your brain). The story thus far revolves around Frank Castle, who, for the last several millennia, has been imbued with the Spirit of Vengeance by Mephisto and a healthy dose of cosmic powers by Galactus, resulting in him gallivanting around the galaxy in search of the wicked to punish (or just someone to talk to).
After a spell as the Black Right Hand of King Thanos, Castle finally meets his demise and heads to Valhalla, where he is promptly kicked out for being… well, being too Frank Castle-y (the guy isn't the easiest person to get along with). Granted the chance to be sent back to anywhere and anytime he wishes by the Asgardians, Castle, being the ever-vigilant voice of compassion, decides to head back to when Thanos was a baby and stop his reign of terror before it ever has a chance to blossom.
Unfortunately, it turned out Baby Thanos was too cute, even for a cold-blooded Spirit of Vengeance. And in all of Frank Castle’s infinite wisdom, instead of snuffing out the Mad Titan, he decided it best to rehabilitate him (let that sink in for a minute). Despite not exactly leading by example, his plan worked. The results, however, were not what Castle had hoped for. It turns out the severity of punishing the wicked for their transgressions varies wildly depending on who is administering the punishment. Despite the Punisher's broken rationale, he still has a moral code. Just because Castle doesn't like someone, or maybe sees them as an eventual threat, they're not going to catch a bullet unless they act out violently.
Thanos, on the other hand, obviously sees things a bit differently. In the world he has built under the tutelage of his adoptive father (quick side note: seeing Thanos call the Punisher "dad" might be one of the most surreal things we've seen in comics in quite some time) is far more brutal than Castle could have imagined. Those who have been deemed wicked by Thanos are relegated to an inferno from which they can never escape. The Mad Titan argues that leaving someone to die and taking their lives are not one in the same, which is reasoning he learned from his "father." The argument between Castle and Thanos only highlights the failings of both of their worldviews, and, more importantly, it makes us question our own.