Archeological confirmation

Christian apologists often cite archeological corroboration of various Scriptural customs, persons, events, &c. But on the face of it, this appeal cuts both ways. If archeology is in a position to confirm Bible history, does that mean archeology is in a position to disconfirm Bible history? 

Indeed, critics of the Bible cite examples where the archeological record allegedly contradicts the Bible. So where does that leave the evidentiary value of archeology in Christian apologetics?

1) To begin with, critics usually mount an argument from silence. They point to the lack of archeological evidence for various Biblical narratives or references. That, however, doesn't contradict Scripture. So the objection involves a bait-and-switch.

In addition, we wouldn't expect an abundance of archeological corroboration. Most of the evidence never survived. Moreover, place-names change over centuries, so identification can be difficult. 

2) But there's another issue. For these are not symmetrical claims. If, say, Josephus and the NT both refer to John the Baptist, that demands a special explanation. It's highly unlikely that both would accidentally refer to John the Baptist. Rather, there must be a reason for their correspondence. 

In principle, there are two potential reasons why two (or more) independent accounts refer to the same thing:

i) They refer to the same thing because they are based on the same event. A common event accounts for independent records of the same event. Because it really happened, it was reported. Indeed, reported in more than one source.

ii) In some cases, they may refer to the same thing because they share a common source. Even though two accounts may be independent of each other, they may be dependent on the same underlying source.  

In any case, their agreement commands our attention. It's impressive when two independent accounts report the same thing. 

3) But if they disagree, that doesn't demand a special explanation. That may simply mean one had a better source of information than the other. By itself, their disagreement doesn't cast doubt on one account rather than another. One account can be true, even if it's flatly contradicted by another account. For instance, a court historian may say the king always wins, even if the king lost. 

By contrast, if two different accounts correspond, this strongly suggests that both accounts are at least approximately correct, for it's not just a coincidence that two independent accounts refer to the same thing–as if they just so happen to imagine the same thing. Usually, an actual event gave rise to both accounts.