First, consider this graph of the monthly export totals from the U.S.:
After dropping sharply during the recession, exports came roaring back. However, their overall rise has really stalled first around the $130 million/month area. Also note that in the latter half of 2012, the overall increase was weaker than before. This time it corresponds to the weakness in the EU.
On the ISM manufacturing index, note that we see a drop in early 2011. There is a slight downtrend from that time to now, with the numbers currently fluctuating around the 50 level.