as soon as vs if only

as soon as

• Used other than figuratively or idiomatically: see as, soon. 

• Used to indicate that the first action mentioned is as likely as, or is preferred to, the second action mentioned. 

• At the moment when; immediately after. 

• Used other than figuratively or idiomatically: see as, soon. 

if only

• Used other than figuratively or idiomatically: see if, only. 

• I wish that; signifies a wish or desire for the present or the future. 

• I wish that; signifies a regret about an action in the past. 

• Even if for no other reason than; only just.