Image via Shutterstock Donald Trump and John Bolton
Image via Shutterstock

Plus three other things you need to know today.

John Bolton says he’ll participate in impeachment proceedings if asked

In a statement posted on his website on Monday, the former national security advisor said he would, in fact, testify in Trump’s impeachment trial if subpoenaed by the Senate. Senate Majority Leader Mitch McConnell, however, has indicated he’s not interested in hearing from any more witnesses, citing precedent set in then-President Clinton’s impeachment trial in 1999.

Pentagon says no to strikes on Iranian monuments 

President Trump’s proposed targeting of Iranian cultural and world heritage sites goes against the laws of armed conflict, said Defense Secretary Mark Esper at a Pentagon news briefing Monday. Trump’s threats prompted across the board outcry, even from such staunch allies as British Prime Minister Boris Johnson and South Carolina Sen. Lindsey Graham. Esper also denied that U.S. troops would withdraw from Iraq after parliament passed a resolution expelling foreign troops. 

Julian Castro endorses Elizabeth Warren

Just days after ending his campaign, the former secretary of Housing and Urban Development appeared in a video endorsing Sen. Warren. The two are scheduled to hold a rally together today in Brooklyn, fueling talk of Castro as a potential running mate.

Former Trump nominee resigns as FEMA head

Jeffrey Byard, head the Federal Emergency Management Agency (FEMA), tendered his resignation Monday to reportedly pursue another professional opportunity. The Trump administration has been plagued by nominees and appointees leaving their posts: The Washington Post’s online tracker reports that 168 vacant positions do not have nominees.