mexican durg cartel have killed over 293 americans

1. Because as history demonstrates prohibition works so well...
2. It may be madness but people have right to be mad, its their body, its their right to shoot whatever they fancy up their veins.

why should clean living decent folk have to pay for the treatment of these ****wits when things inevitably go wrong ?

Because we have universal healthcare and we constantly pay to treat people for their bad decisions: else should we stop paying for heart treatment of obese people or people who pass out after drinking or those who break traffic laws and get involved in car crash... what about people who get injured during adventure sports?
Universal healthcare by definition must be accessible to everyone regardless of their choice and should not be used as excuse to control people's lives. Even going from purely economic point of view, it is quite unlikely these druggies will survive to old age so we saves money on old age care and pension: give size of which I am quite sure balance is positive.

the golden age of universal healthcare is in the past. wake up and smell the coffee ( decaff of course ). irresponsible behaviour will be rewarded less and less in the years ahead.

Time and place for decaff coffee is never and in the bin.
Anyway, most injuries and illness can be attributed to irresponsible behaviour so where do you draw the line.

what on earth are you on about ? how can you say that children with leukaemia have been irresponsible ?

Most being the operative word. 400 cases a year does not make 'most'.

http://america.aljazeera.com/opinions/2014/10/isil-vs-mexican-drugcartelsunitedstatesislamophobia.html

and that was just from 2007 to 2010

but no america should be more concerned with isis, an organisation who will never step foot on US soil

instead of the cartels

who actively control certain areas in arizona

who operate freely in mexico and are constantly in america

but then again the blood thirsty liberals and drug addicts need their drugs

https://www.youtube.com/watch?v=OAfEq80YlWU

Look what I found.
http://mic.com/articles/105510/11-months-after-marijuana-legalization-here-s-what-s-happening-to-mexican-cartels?utm_source=huffingtonpost.com&utm_medium=referral&utm_campaign=pubexchange_facebook

So if this article is anything to go by, you're quite right: Americans should be more concerned with cartel killings than ISIS killings. Unfortunately, you seem to be using the cartels activities as "evidence" that drugs should remain illegal. Well guess what? If they remain illegal, then killings will continue. If there's no profit, there's no business, and if there's no business, then why bother killing people over that particular branch of business?

Also, 293? Lulz. If we're just gonna throw statistics around:

"Senior researcher of Human Rights Watch, Allyson Collins, wrote an article on police brutality in the U.S. In it, she states that “the Justice Department receives over 12,000 complaints each year of law enforcement abuse.”

http://guardianlv.com/2014/08/number-of-unjustified-police-killings-is-uncounted/#y27ZtrgQd8LKkp38.99"

So by your logic, the American public should be much more concerned with the people who are employed by their government to protect them than they should be with Mexican cartels.

i don't see how drug users can avoid thinking about where their nose candy etc comes from... do they think that their local supplier imports it from some smiling Fair Trade farmers ?