As the Oval Office changed hands from one party to the other, there hasn't been all that much difference in foreign policy regimes. So the neo-con takeover of US foreign policy under Bush was an interesting development.
More interesting is that there still hasn't been all that much difference.
Wes Clark reveals he heard, on roughly September 21, 2001, that Bush had a plan to take out 7 countries in 5 years. Iraq, Syria, Lebanon, Libya, Somalia, Sudan, and Iran.
He told this story about 6 years later. He called it a policy coup.
That was 5 years ago. Since that time, largely in response to the Arab Spring, we “liberated” Libya. We’re preparing to (if have not already done so) arm al-Qaeda related rebels in Syria. We’re inventing reasons to sanction a Lebanese terror-related political party. We’ve been violating sanctions to wage war in Somalia, including with drones, and have fiddled with several incarnations of government. And our Iran sanctions–which are fairly clearly about regime change–are really beginning to hurt the Iranian people.