The Defense Department says it remains ready to work with Congress on questions about previously stalled U.S. military aid to Ukraine, but the White House's assertion that the impeachment inquiry into President Trump is illegitimate could leave DOD unable to respond to a subpoena it received from three House committees. "As we've stated previously, we are prepared to work with Congress and other relevant parties on questions related to the issue of Ukrainian aid as appropriate," DOD spokeswoman Lisa Lawrence...