The thing is, most people probably take up smoking before they are 21. Once you're 21 if you don't smoke already there's a very slim chance you'll ever take it up. So, arguably setting the buying age at 21 might be effective at reducing the youth uptake of smoking and getting some people over the hump into adulthood where they are unlikely to ever start up.
On the other hand, loads of kids take up smoking well before they are legally able to purchase cigarettes, so does an age limit on cigarette sales actually work?
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
Jimi Hendrix
