Just my opinion of course, and it does seem logical
to me, however I am open to discussion on this.

Roy,

We know that adding CO2 to the atmosphere causes warming, and we are
adding CO2 to our atmosphere so that is likely to cause warming. Just
because, when changes in CO2 caused climate change in the past, those
changes were not instigated by man does not mean that if man increases
CO2 in our atmosphere then the climate will not warm.

CO2 is not the only thing that causes warming. Changes in the Earth's
orbit brought us out of the last glacial period, although that exit
seems to have been accelerated by rising CO2 levels. If changes to
the Martian orbit are causing its polar ice to melt and release CO2,
then its climate change may be fast too.

Something that is not often mentioned is that the peak of the warmth
during this interglacial was about 5000 years ago. By rights we should
now be advancing into another glacial. It seems that land use changes
kept CO2 and CH4 levels high, and so this warm interglacial has lasted
longer that the previous ones. Hence the rise of civilisation over
the last 10,000 years, but we have now gone too far.

Cheers, Alastair.
http://www.complexclimate.org