The confrontation between Donald Trump and the House of Representatives — in which Trump is doing everything he can to block the House’s normal oversight powers — has me thinking about impoundment.

That’s an old Nixon-era controversy, in which President Richard Nixon tried to not spend – “to impound” – money that Congress had appropriated for some programs Nixon opposed. He wasn’t the first president to do it, but the scope and scale of what he tried to do were beyond anything that his predecessors had attempted.

Eventually, Congress made it clear it wouldn’t stand for this, in part by passing a new budget law in 1974. That same Congress also passed the War Powers Act after Nixon had bypassed Congress in expanding the Vietnam War into Cambodia. Again, other presidents had done similar things, but Nixon took it a step further.