There are so many more steps that can be taken before one begins forcing eating habits upon entire cultures. I think while the cause is correct, telling people what they can and cannot eat or how often/much is a recipe for abject failure. Education is a better method so that people will make their own choices and lower the demand for meat.
First and foremost, mandating to citizens that they eat less meat is an unreasonable intrusion of government into citizens' lives. What you eat yourself and feed to your children is a decision that people have been making for thousands of years without the assistance of authority figures. A secondary concern is that "eat less meat" is an overly broad directive. Each type of meat has its own environmental problems. Should we worry more about cattle producing greenhouse gases or over-fishing in the Pacific?
I think they could try, but humans have been eating meat for thousands of years, and pretty much the entire population of the world enjoys eating meat, (except where religion stops them,) so I don't think that anything the government does is going to change people's meat eating habits very much.
There is no solid science showing that a reduction in the amount meat consumed would result in a reduction in greenhouse gases and help to prevent global warming. Since there is no clear data governments should not restrict or otherwise modify the consumption of meat and meat products. This would only go the hurt the small farmer.
No, this is not going to help out the problem that we are having with global warming in the least amount. It is the amount of pollution that we have that is making global warming such a huge issue right now, and is not a thing to do with meat.