﴿ ذَٰلِكَ بِأَنَّ ٱللَّهَ مَوْلَى ٱلَّذِينَ ءَامَنُوا۟ وَأَنَّ ٱلْكَٰفِرِينَ لَا مَوْلَىٰ لَهُمْ ﴾

“This, because God is the Protector of all who have attained to faith, whereas they who deny the truth have no protector.”

That granting of victory to the believers and the vanquishing of the disbelievers is because God is Patron Ally and Helper of those who believe and because the disbelievers have no patron.