It is fair to suggest that there is a day, week or month to recognize or acknowledge just about everything under the sun: facial hair, food stuffs, odd sports and not-so-national pasts times.
National Back Issue Month, a celebration I only became aware of thanks to the FB posts of a fellow frequenter of the same local comic store as I (actually, he started the month long activity to reinforce and remind collectors of the love of older comics in the face of DC Comics' September reboot of their entire line-up). In the spirit of silly celebratory calender caveats, I will also be "celebrating" National Back Issue Month daily by sharing comics from my back issue long boxes and explaining (briefly) the issues significance to me. And no, you haven't missed Days 1 though 4, it's just that I've only just now gotten around to starting this series of posts albeit four days late.
Issue 200 of Fantastic Four was the starting point for what would become my (to this point) life long love affair with Marvel's First Family. While the next issue, 201 (featuring the robotic villainy of Quasimodo!), was my first actual comic book purchase, issue 200 was the first "back issue" I bought... roughly a month after it came out, but a "back issue" nonetheless. The story, "When Titans Clash!" was script by Marv Wolfman and featured art by Keith Pollard (breakdowns) and Joe Sinnott (finishes). The amazing cover was done by none other than Jack "The King" Kirby and Joe Sinnott.
Published in 1978, when I was nine years old, the epic "fight to the finish" between Doctor Doom and Mister Fantastic had everything I wanted from comic books: action, adventure, and escapism. Leafing back through the pages the story (which at its heart is about the FF assisting in overthrowing Doom's government in the interest of "nation building") and characetrization (Doom's anger at having his own son--clone--destroyed) perhaps not surprisingly has much more depth and resonance than what is published in the current issues.