Warning! Spoilers ahead for Star Trek – The Mirror War #4!
If the many holodeck disasters in Star Trek have taught fans anything, it's that biological lifeforms can die in these holographic simulations if the safety protocols are disabled for whatever reason (usually by mistake). But the comics just revealed that even the holodecks themselves can be damaged.
In the Star Trek upside-down mirror universe, the ISS Enterprise-D's historian Whalen sabotages the evil Captain Jean-Luc Picard's holodeck program in an attempt to assassinate him by not only disengaging the safety protocols as per usual but allowing the actual holodeck to sustain damage in Star Trek: The Mirror War #4 by writers Scott and David Tipton, artist Gavin Smith, colorist Charlie Kirchoff and letterer Neil Uyetake. Before the holodeck is destroyed, Picard leads Whalen on a car chase (in what appears to be a 21st century city) and knows the area well enough to lead his assailant into an area that's hard to maneuver through, causing the assassin's vehicle to flip over in a fiery explosion that rips a hole in the holodeck.
Of course, in the mirror world, betrayal and assassination attempts are commonplace in the upside-down Federation, so the evil Picard and his crew don't bother investigating. It's also quite likely that only such a functionality exists in this other world instead of in the normal universe, as it's impossible to imagine that the Federation fans are familiar with would ever allow engineers to create one. But the evil Federation—known as the Terran Empire—are more akin to Klingons, so it's understandable why an ISS starship would be equipped with such a functionality. Conversely, this isn't the first time in Star Trek for a bad actor to sabotage a holodeck. In Star Trek: Voyager, a Cardassian operative named Seska who was genetically altered to appear Bajoran was forced to join the crew of the eponymous starship and eventually caused Voyager's holodeck to malfunction before her escape in the episode "Worst Case Scenario."
How the Mirror War's holodeck accident affects the actual holodeck in the real-world mirrors how some holodeck lifeforms gain sentience in the TV franchise, allowing these holographic characters to come to the conclusion they are part of a simulation and sometime even attempt to take control of the actual ship outside of the holodeck. The first instance of this occurs in The Next Generation after Geordi La Forge improves a Sherlock Holmes-themed holodeck program for Data by creating an adversary who can challenge his android friend. The result is a version of Professor James Moriarty who realizes he's a hologram and tries to commandeer the ship.
Although holoprograms haven't destroyed actual holodecks in the regular Star Trek universe, fans can assume that the Federation can emulate this functionality. One of the major subsystems of every holodeck incorporates transport-based technology that can create actual real-life props and other similar items out of raw material through a process known as transporter matter conversion. But because the Federation isn't as destructive as its evil Empire counterparts in the mirror universe, there hasn't been an instance of this technology in the TV franchise ... yet.