double down | verb

a) To double ones wager: War criminals like, Hillary Clinton, John Edwards and Barack Obama all wanted to get out of Iraq. They all wanted to double down in Afghanistan, look at how that worked out.
b) To double or significantly increase a risk, investment, or other commitment: Retarded day traders used leverage, doubled down and got wiped out.
c) To justify an erroneous assumption to weak-minded fools that they need to support an unpopular idea: We need to double down on Ukraine.