Ron Paul - 'The US has defaulted 3 times in the past '

From Bloomberg.com:

The U.S. government defaulted at least three times on its obligations during the 20th century.

-- In 1934, the government banned ownership of gold and eliminated the right to exchange gold certificates for gold coins. It then immediately revalued gold from $20.67 per troy ounce to $35, thus devaluing the dollar holdings of all Americans by 40 percent. (actually 70%, a convenient typo?)

-- From 1934 to 1968, the federal government continued to issue and redeem silver certificates, notes that circulated as legal tender that could be redeemed for silver coins or silver bars. In 1968, Congress unilaterally reneged on this obligation, too.

-- From 1934 to 1971, foreign governments were permitted by the U.S. government to exchange their dollars for gold through the gold window. In 1971, President Richard Nixon severed this final link between the dollar and gold by closing the gold window, thus in effect defaulting once again on a debt obligation of the U.S. government.........read story in full