First offense for being behind the wheel of a car while drunk should be mandatory lose of license even if there wasn't an accident.

In the UK that is the case. You lose your licence automatically for 12 months if you try to drive when over the limit, and you are spotted. The fact that there might not have been any kind of accident or driving error doesn't alter that. You might just have been stopped because you had a rear light which was a bit dim. You can get fined or jailed as well, dependimng how far over the limit you are.

Here's a page with deatils about the penalties and so forth. The limit? Two pints of beer will likely put you over it.

All seems reasonable enough to me. They're only trying to keep us from killing ourselves and other people.