AS THE effects of the financial crisis ripple out into the wider economy, businesses are struggling. With access to credit all but choked off and global demand falling, firms are keen for any help they can get. America's big companies have a friend in John McCain, who says he will cut the top federal corporate tax rate from 35% to 25%. Once state and local taxes are added, the combined rate amounts to an average 40% of profits, the second highest in rich countries. Over the past decade, corporate-tax rates have fallen considerably, especially in the countries of the European Union.