The New York Sun asks, and offers a list of unifying ideas. The top item on their list concerns taxes.
Reductions in top marginal tax rates provide incentives for growth and lead to greater government revenues in the long run. That is not always the case. There is a point on the Laffer Curve at which tax cuts on the top margin stop generating increased income, but we are nowhere near that point now.
Presumably what they mean is that the top income tax rate is higher than the revenue-maximizing rate, but I’m not sure why they think that it is. Bush’s tax cuts appear to have caused revenue to be lower than it would otherwise have been, which suggests that we’re already below the revenue-maximizing tax rate.