When an economy is normalizing, it is reasonable to reduce expansionary measures, such as those introduced after the crisis of 2008. Because the Fed has clearly communicated that it will move gradually toward less expansionary policies, its credibility would be damaged if it did not follow through.
支持升息的理由很充分。美国经济正在重获动力。国际货币基金组织（IMF）预测2015和2016年增长率为3%，对应通胀率分别为0.1%和1.5%。当经济开始正常化时，减少扩张政策（比如2008年危机后实施的那些）再合理不过了。美联储早就明确表示它将逐渐减少扩张性政策，因此，如果它不那么做，信誉就会收到影响。