If we could achieve our aims by merely wishing, life would be very easy.
The archaic conjunction ‘an’ means the same as ‘if’. It comes on one of Mother Goose’s Nursery Rhymes:
If ‘ifs’ and ‘ans’
Were pots and pans
There’s be no work for tinkers!
Tinkers are menders of pots and pans, and if ‘if’ were magically transformed into a new kitchen utensil every time it was said, there would be no need for their service. But there is always an ‘if’.