Extended Republican leadership
preceded 2 of the Unite States (and the world's) financial collapses.
In the almost 98 years from May of 1919 through January of 2017 (when tRump was sworn in) the Republican party only controlled the law making of the United States for 2 extended periods of time. Both times their policies led to financial collapse.
They controlled both houses of Congress from May of 1919 through to the 1929 crash in October of 1929 (10 years, 5 months - the Presidency for 8 years, 5 months) and from January 1995 through to the crash in September of 2008 (13 years, 8 months - the Presidency for 7 years, 8 months). They had 2 chances to govern, both resulted in financial failures. No politicians or bankers went to prison after the 1929 crash and only 1 banker did so after the 2008 crash.
After the 1929 crash they were denied control of the Senate for 46 of the next 50 years and out of control in the House for 60 of the next 64 years. Hopefully the backlash to the tRump term will result in a similar history but without the financial prodding.