The M1911 has a flawless pedigree. It was developed specifically to kill muslim fanatics who would survive .38s and go on to kill the shooter.
There is no doubt that the .45 is far superior to the old .38 Army round. The fact is the 9mm is also far superior to it.
That old .38 round was extremely weak with only 150 ft. lbs. of energy. The 9mm and .45 in military loadings are both in the 350 ft. lbs. range.
That certainly is a compelling reason to reissue them.
I assume Force Recon experience with the M-45 MEUSOC has something to do with the decision.