The next group of Muslim mega-terrorists will enter the USA the same way the last batch of 19 did, namely with genuine, legal U.S. visas.
Nothing has changed since 9-11-01 that would prevent them from doing so. Visa adjudication has not gotten tougher, U.S. green cards are still being sprinkled over the middle and near east to the tune of 100,000 new Muslim immigrants yearly, and any of the millions of Mohammedans with a EU or Canadian passport can just waltz in without even needing the proforma Consulate or Embassy appearance.
Fingerprinting? A great anti-document-fraud tool, and great too, for catching Mexicans with 6-year-old DUI warrants, but not something that's going to keep the next Muhammad Atta out of our homeland.