Many different countries rely on consumer spending in the United States to support their economies. Many domestic companies also rely on strength in foreign economies to support themselves, meaning that U.S. stock markets could see a further slide if other countries are significantly affected by any problems in the United States. A global slowdown isn't good for anyone...

From Reuters:
Mexican consumer lending by banks, expected to be a key motor of the economy this year, grew 19 percent in December, a slower pace than in previous months, according to a report on Thursday. Consumer credit barely existed in Mexico when its economy was dragged down by the last U.S. recession six years ago.  Mexico cut its economic growth forecast for 2008 on Wednesday to 2.8 percent from 3.7 percent as a possible recession loomed in the United States, its top trade partner.