During centuries, energy/resource consumption gradually grew. This is not a problem per se if new ways to acquire and exploit new resources are invented. But what is dangerous is
a) too fast growth of consumption
b) lack of reserves
c) lack of flexibility
In history, there were good times, when consumption grew, and bad times, when cultures unable to change their habits collapsed. Some civilisations, like ancient Egypt or China, were able to recover from the hard times easier than others, who didn't survive crises so well or even at all. Why?
This seems to be closely connected with the basic orientation of the culture. For example in ancient Egypt, the biggest goal was to "live forever" - their growth aimed to produce tomb treasures, which could be looted and reused in bad times. There are theories that people could legally loot their ancestors' tombs if the ancestors didn't bless them and protect them - the dead (and especially dead kings) were believed to have power to ensure blessing of good crops and of freedom from enemies. Whether these theories are true or not is a question for History.SE, the conclusion is that such civilisation was oriented for long term survival, not for temporary growth and that it survived thousands of years, at least three big crises and many smaller ones.
On the other hand, there were many cultures even more oriented for growth than our civilisation - they were mostly war-like states, like most of Dark Age kingdoms. Constant war, winning, loot and new vassals were requirements of their existence, so few such states survived, and many ceased to exist in few years, with just few major defeats. The culture survived the end of such states, but it couldn't stay long in with such orientation on military expansion.
Our civilisation is more similar to the Dark Age than to ancient Egypt, but of course better - it's oriented on economic and technological growth, which are more resistant to temporary failures than military expansion. But not so much - recent economic crisis shows it's drawback. And there are ecological challenges, oil peak and so on. Existence of this forum shows that there are people who try to make the civilisation sustainable, but the idea that we don't need reserves, because technological growth will solve everything decreases flexibility of our civilisation. How shall we survive the moment of opening eyes and seeing that oil is too rare to be cheap, and that other sources are too expensive for our potlatch?
So, economic growth can be sustainable, but
a) must be slower
b) must be backed up by better reserves for bad times
c) must not be a basic aim of the civilisation, since orientation to growth is in conflict with flexibility and willingness to decrease my consumption for the good of the whole. This is a matter of values - if most people are egoists who would rather accept risk of collapse of civilisation later than to decrease standard of living now, than growth is not sustainable and will eventually lead to disaster, but with certain minimal percentage of altruists willing to decrease their ecological footprint, even groth can be sustainable. That's why I'm here.