Helping FReepers to have an informed opinion of this issue, which I'm interested in.
1. Has the Earth ever been warmer on average than it is today?
Sure, it has been a lot warmer. There used to be no ice caps, if you want to go back that far. In the recent past, it appears that the peak of a couple of the previous interglacials might have been slightly warmer.
Does the Earth go through hot and cold cycles and is it possible that this warming trend is just another cycle?
The Earth clearly goes through warming and cooling cycles, glacial/interglacial periods being the most recent and most significant. The Holocene has been very stable with little evidence of a strong cyclical influence. The preponderance of evidence indicates that the current warming trend which began in the mid-1850s (about when the Little Ice Age terminated) is not predominantly part of a natural cycle, particularly the warming since the mid-70s. The elimination of natural cyclical influence as part of the cause of the warming is one part of the attribution to human activities.
Are you aware of the cooler period of 30 or so years before the 1970's? You forgot to mention that. Increased sun spot activity since then? You forgot this too. The thickening of Antarctic ice on most of the continent? Bet you are real good at ignoring this. Mann's bogus hockey stick model? At least it seems you are aware of Mann's fraudulent attempt at fact manipulation. If a scientific theory is valid, fraud is not needed to convince others. These are just a few of many reasons to doubt the GW agenda suggesting man's influence is the major factor of climate change. What about the fear of so-called GW scientists to debate dissenters? Why are all dissenting scientists ignored and not given even a tiny potion of the debate stage by the media? These objective scientists are attacked and derided in the media and schools and threatened not only career wise, but physically also. Many are afraid to speak out until they are retired or don't need funding anymore. Some must even keep their whereabouts unknown to not be physical attacked or have their homes vandalized.
When a theory is bogus and based on junk science, the only way to keep it alive is to control the dissemination of info the way communism does. The GW agendists are doing this with control of scientist's grants, the schools and the media. They copy communist tactics most efficiently. And/or are actually communists themselves pushing a part of the communist plan to destroy America economically devised prior to the mid 60's.
A scientist I trust more than anyone else on this planet works in a complex with three labs whose goal is to convince the public of GW being man-made. Most of these people are driven by their blind hatred of America and Bush and their greed to receive their next university/tax dollar funded grant (which they will only get if they promote the GW caused by man theory). These labs aren't exactly overflowing with Einsteins and nepotism is an epidemic which allows for people being hired based on partisan beliefs rather than scientific credentials. In other words - many idiots that will only see what fits their preconceived notions. The most common practice is the hiring of professor's wives with different last names so it's not obvious. Not only are they pushing biased science on the ignorant masses, but they are ripping off tax payers too. Any dissenting scientist need not apply for grants to study GW, regardless of their credentials and brilliance. Those who control the grant process are very liberal, anti-American and politically motivated to no end. All 'inconvenient' facts are ignored by these agenda driven despisers of the truth.
Stop drinking the kool-aid. You'll freeze your tongue off (tongue in cheek). Or are you being paid to push the GW BS here on FR???