The motive that is common to al-Qaeda, ISIS, and other Islamic extremist groups is the following;
Create a government based on religion.
The extremist groups like al-Qaeda and ISIS believe that they are fighting in the name of Islam and the Islamic teachings. They want to create a government on the basis of the Sharia law.
Grover Cleveland!
Grover Cleveland was known for personally answering the phone in the White House.
Even though Harding, Coolidge, and Hoover were all presidents elected to office for the Republicans, Hoover wasn´t really a conservative.
As the economy suffered due to the infamous stock market crash of 1929, Hoover explored non-conservative policies that his predecessors wouldn´t support. He expanded public works, signed into law the high peacetime tax increase and signed a tariff that would end up hurting foreign trade.