In that case, why do we have any ice caps at all?

There is very good evidence not only for feedbacks but also for sudden regime changes in the climate. For example, the Paleocene-Eocene thermal maximum saw ocean temperatures in the arctic rise to 20°C. This dramatic climate shift led to a mass extinction and is believed to have been caused by a release of CO2 and/or methane into the atmosphere.

The existence of feedbacks is extremely well-established and observationally verified. The existence of the potential for sudden regime shifts is clear. Your arguments are based on wrong assumptions.

Leif Svalgaard says:

“Jack, the issue here is that it is almost dogma that the sun is the cause of the climate swings the last few thousand years [LIA, MWP, etc]. This is so because we don’t know what else could do it [certainly not man-made CO2, if we except that last 100 years]. The problem is that the latest solar data seem to indicate [and this is still controversial] that the sun varies less than what we thought just a few years ago, so if we will maintain that the sun is still the culprit, then we have to crank up significantly the sensitivity of the climate to solar forcing.”

http://www.climateaudit.org/?p=2679#comment-205697

The new solar data pretty much shreads the IPCC argument that CO2 is the only known explaination for the current warming since CO2 cannot be blamed by default until someone comes up with a credible explaination for the MWP and LIA and demonstrates that the same cause is not at work today.

My gut feel is random variations – chaotic weather patterns that vary over centuries instead of days.

Inevitably, the fallback position of the “warmers” is that (1) I’m arguing against essentially all of the world’s scientists; and (2) anyone on my side of the debate either has some kind of connection to the oil industry or is published in a non-peer-reviewed journal or both.

By the way:
From Mirriam Websters: “usage Irregardless originated in dialectal American speech in the early 20th century. Its fairly widespread use in speech called it to the attention of usage commentators as early as 1927. The most frequently repeated remark about it is that “there is no such word.” There is such a word, however. It is still used primarily in speech, although it can be found from time to time in edited prose. Its reputation has not risen over the years, and it is still a long way from general acceptance. Use regardless instead.”