Conor Sen: Trump’s economic gamble might make sense

President Donald Trump is conducting a risky experiment on the U.S. economy: He’s allowing the government to run large budget deficits — some of the largest ever outside wartime or recession — in the hopes that this will somehow put growth on a higher trajectory. Irresponsible as that might sound, it actually makes some sense.In the long run, economic growth is a function of two variables: population and productivity. For decades, America had plenty of both. Birth rates were am