Why do some Christians think it's not a sin to charge interest?

[This article](http://www.patheos.com/community/slacktivist/2010/05/29/sex-money-part-1/) presents the view that Christians should not charge interest on loans. As evidence, it cites [Nehemiah 5:9-10](http://www.biblegateway.com/passage/?search=Nehemiah%205:9-10&version=KJV) : > **9** Also I said, It is not good that ye do: ought ye not to walk in the fear of our God because of the reproach of the heathen our enemies? > > **10** I likewise, and my brethren, and my servants, might exact of them money and corn: I pray you, let us leave off this usury. In light of this, why do many Christians think it is _not_ a sin to charge interest?