You've got to add $5 trillion to the debt or we can't have a border

What's the modern argument for giving tax cuts to billionaires? Before, it was trickle down economics... they create jobs, so they having more money meant more jobs for us. But now they just import jeets and other third worlders for all job creation. So what benefit is it to the citizenry to grant a tax cut to a billionaire now? Is there any argument at all?