Tax cuts have big impact in good times, but not in bad.
Tax cuts in the US have a bigger impact on the economy when times are good compared to when times are bad. This is because tax cuts encourage people to look for jobs, reducing barriers for companies to hire new workers. Financial market disruptions have a larger and longer-lasting negative effect on output than positive ones. The financial crisis of 2007-2008 can explain a significant portion of the gap between current GDP and its pre-crisis trend.