You have the causality backwards. There is always "speculation" anytime there is an opportunity to buy something that one thinks can be resold at a profit. Th

You have the causality backwards. There is always "speculation" anytime there is an opportunity to buy something that one thinks can be resold at a profit. The real estate bubble, by inflating the prices of homes, increased the opportunities for successful speculation. The main cause of the bubble was cheap mortgages which allowed the price inflation to get so out of control. The speculation was a result of the problems, not their cause. And most real estate speculators were hammered worse than anyone else, except their creditors, when the bubble burst - always a risk with speculation.