No need for hindsight. There had been five previous events of fuel tank penetration.
Indeed...and this was looked at during the original trail:
According to Heath, one witness had outlined to the court the US National Transportation Safety Board's investigation in the 1979 Concorde accident at Washington Dulles when a fuel tank was ruptured on take-off after a tyre-burst.
"None of the NTSB's recommendations were aimed at armouring the wing - they were quite satisfied with the actions taken to prevent a tyre or wheel breaking up and debris puncturing the tanks," (Tony) Heath says.
The previous penetrations were I believe caused by substandard tyre design. This was rectified and no longer deemed an issue. No one foresaw such an issue would arise agian...the aircraft was lost due to FOD and the subsequent misfortune of not correctly identifying the source of the fire; not because it was an un-airworthy aircraft.