April 9 (UPI) -- In a matter of weeks, workers on opposite banks of the Paraguay River are expected to guide the final sections of a new international bridge into place, closing the last gap in a structure that has taken years to build and decades to imagine. The moment will attract cameras, official speeches, and a tempting conclusion that one of South America's most ambitious integration projects is finally complete. That conclusion would be premature. The bridge linking Porto Murtinho in