Question to all Americans: why do you refer to vehicles and ships as "she"?

[rado84]

It's not only Americans.

Seriously though, if you had a very intelligent robot, wouldn't you refer to it as a he/she, depending on what you would like most to imagine it as? It humanizes something you rely on. It's a natural thing to do, really.

Probably not but so far from all the people I've ever met and/or talked to through the internet only Americans have done that.

I wouldn't. I stick to the grammatical rules. I've named my computer after a pretty boy I used to know but when it comes to pronouns I alway refer to it as an "it", not as a "he". I mean in English. In Bulgarian it's a little different, which if anyone's interested, I could explain.