Exactly. If you wanted an armed LPD that can do its own fire support, it would have to be centered on VLS, for range. Which isn't a horrible idea - the San Antonios might still eventually be fitted with TLAMs. But it's not a matter of direct fire - it's just a matter of having a few more missiles as part of your overall fleet, which could be useful, if you already have the silos installed.
Can’t the San Antonio class already launch a shorter range surface to surface missile? Can’t remember what it’s called.