The 2008 Wrangler Owner's Manual indicates the key must be used to unlock the steering lock when being towed. It says the key should be in the ACC position, but many people turn it past this to the ON position that that will activate more of the electrical system. The recommended way of disabling the system is to remove the negative battery cable and many people use a simple cut-off switch. I've found the ones you can get that have a small knob tend to corrode over time and you're constantly having to remove and clean them. I use an enclosed one now that has a big red plastic key and it has eliminated all my corrosion problems. If all you want to do is remove a fuse though, the one to look for is the IOD fuse.
Bad switchGood switchBTW, this only applies to a Wrangler with 4wd.