There are three ways to reduce a huge budget deficit such as the one that we have in the United States today.
First, the government could increase the amount of revenue that it takes in in taxes by raising tax rates or otherwise changing the tax code. Second, the government can reduce the amount of money that it spends. Finally, the nation’s economy could grow. When the economy grows, taxes naturally rise because people and corporations are making more money. When the economy grows, spending naturally decreases as there is less need for things like welfare spending and unemployment compensation.
Of these, then, the best thing to do is to get the economy to grow. Raising taxes can potentially hurt the economy as it takes money out some people’s hands. Lowering spending can do the same. Only economic growth can lower deficits reliably. Sadly, it is not at all easy to ensure that economic growth happens. If we knew for certain how to make growth happen, we would already have done so.
Therefore, it seems likely that the best way to reduce the deficit is to raise taxes a little bit, decrease spending to some degree, and enact as many policies as possible that might lead to economic growth.