CLOUD CHANGE EFFECT LIKELY CAUSE OF MUCH OF THE EARTH'S WARMING

I wonder why there is so little attention paid to research into the effect of changes in cloud cover. It seems an obvious thing to be checked, but it seems the politics has come down on one answer which is CO2 increase and nothing else is allowed to blur the picture. 

Another New Study Links Modern and Past Global Warming to Natural Changes in Cloud Clover, Not CO2 - Watts Up With That?