Longing for Martini

I love martini.

Double, on the rocks, rosso of course... not the dry one.

It's been one of my temptings whenever I dine out. But it's very hard to find it here. Neither in the big suppa nor small liqueur shops.

One shop attendant at liqueur shop at Shinjuku told me that martini is a mixture of cinzano and whatsoever, and very easy to make. But onii-chan, I'm simply not the bartender.

Can somebody please tell me why martini is not available in Japan?

(image by: kemangdutyfree.com)