What was principal cause of the 2007 recession?

Subprime mortgages was the principal cause of the 2007 recession.

Hedge funds, banks, and insurance companies led to the subprime mortgage crisis. Hedge funds and banks created mortgage-backed securities. The insurance companies covered them with credit default swaps. Demand for mortgages caused an asset bubble in housing.  

Home prices plummeted, and borrowers defaulted resulting in the 2007 banking crisis, the 2008 financial crisis, and the Great Recession.

richard nixon led the investigation that resulted in alger hiss being convicted of prejury.

the dominoes began to fall. the surrender at appomattox took place a week later on april 9. while it was the most significant surrender to take place during the civil war, gen. robert e. lee, the confederacy's most respected commander, surrendered only his army of northern virginia to union gen. ulysses s. grant

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