As much as you think ordering a cocktail in a pub is appealing, stop, and think for a moment.
I once found myself is a fairly fancy restaurant where on first glance it would be safe to order a gin martini. What I got was a popular Italian vermouth and gin in a highball glass with ice and a slice of lemon.
You ask a pub bartender for a cocktail, and you are riding on the spines of death my friend. Apart from if you are in Brooklyn. You can safely order ANYTHING in Brooklyn.