To enforce.. you need that quaint old concept of trafpol on the lurk!
Since we do not appear to be enforcing current levels - lowering will not really achieve that much. Besides .. French fine at the lower level and ban at the same level as UK.
But we are back to gnawing on that old bone of education. We seem to have developed a culture of "binge and over-indulgence". Nothing wrong with booze so long as you bring up kids to see it as a normal part of decent meal and small sips at a social event. Too many seem to think being drunk/drugged out of mind and body as some kind of "desireable achievement". Could be a form of escape .. as seems to have been case with our foster "headache". (Good news - he seems not to want to drink now ..phew! Perhaps instead of locking these kids up - perhaps a fostered nurture may be more worthwhile.. but then we are an odd lot -- rebels as far as road safety policy goes and a bit on the strict side as parents

)
But a general education about drink and handling drink.. via public information would not go amiss. Most have no idea how much it costs NHS on ambulance services .. who are called out to more injuries caused by drunken tiffs and brawls than anything else since 24/7 drinking was allowed. CC Green of Notts was absolutely correct when he spoke out about it.. from a policing point of view as well.
Heck .. drink to excess costs more to NHS in treatments and time than any road incident.. and effects build up over the years of this over indulgence in drink and drug culture.
My advice has always been the same... if you intend to have even one drink with meal at restaurant or pub.. then get taxi there and back. More relaxing and more of a night out too!
And for heaven's sake .. never ask for a wine spritzer as you cannot control the alcohol strength served up in the drink and because it's mixed with fizzy water.. goes straight through stomach wall into your system - especially if you drink on empty stomach. You also do not think you have drunk that much because of the water down of the taste.