Global Warming and Responsibility

Recently Indian PM spelled out the approach to fight the global warming.
One argument given by Indian govt. to reduce India's responsibility on carbon emissions is that India's per capita emissions are very low.
I wonder if per capita emissions are a good yardstick to measure a country's carbon footprint. Let's examine this in some detail.
Before we start the arguments one thing is clear(something which is often emphasized in climate change campaigns) that global warming has no boundaries. It's effects are universal and not limited to one country ,that is to say carbon dioxide emitted in one part of a world has it's effects on whole of the planet.
When we are taking the effects of emission of a country as a whole we have to consider things other than population. Countries differ in sizes. Therefore one good measure to compare emissions would be emissions per unit area of the country. But in such a case countries like Russia will unduly benefit who have a large area but small population because of hostile climatic or geographic conditions.
Another factor that can be taken into account is the area covered by forests in a country. That can be used for offsetting the carbon footprint of the country. This can be included in carbon trading.
One more factor that can be taken into account is the historical contribution of a country in carbon emissions(for this the start date can be set as the beginning of industrial revolution). This will definitely put more responsibility on developed nations as historically they are the largest emitters.
Now I come to my original point. Why emissions per capita is not a good point ?
Firstly it gives advantage to those countries who have large population.( a large population is not such a good thing for the environment,we all know that).
Secondly in a country like India which has a large percentage of population below poverty line and where wealth is unevenly distributed only a part of the population is responsible for so large emissions (this a general rule. Emissions are proportional to wealth for any nation). Such arguments only promote inefficient technologies.
Therefore a good parameter would be the one which combines all these parameters. (and may be few more that I have missed.)

Well after all is said and done it is the responsibility of every country to fight global warming. The developed countries are best equipped because they have the resources for the R&D efforts required. It's also an opportunity for developing countries like India who are knocking on the door. India and China are rapidly growing economies. It's the time for them to decide what kind of growth they want and what stake the environment has in that growth. This is the time for them to implement solutions to growth needs which are in sync with the environment and nature. In this regard they are better placed than developed countries who have to convert ineffecient infrastructure to be more environment friendly. It is also an opportunity for businesses across the world to come with innovative solutions. As the saying goes "necessity is the mother of invention". It's for the governments and the media to make the companies realize the necessity of action on this front.