Delta Force wouldn't stand a chance. Xavier could telepathically take over their minds and turn them on one another. Jean Grey could telekinetically stop their hearts and deflect their bullets. Iceman could freeze their guns. Nightcrawler would *bamf* around knocking the Deltas out before they could even aim. Colossus is bulletproof and would smack their asses. and that's without Cylcops' optic blasts and the omnipresent Wolverine shish-kebabing them