رُّبَمَا يَوَدُّ الَّذِينَ كَفَرُواْ لَوْ كَانُواْ مُسْلِمِينَ
[15:2]
Often will those who disbelieve wish that they had been Muslims.
Again and again will those who disbelieve, wish that they had bowed (to Allah's will) in Islam.
It may be that those who disbelieve wish ardently that they were Muslims.