No, Pueblo's mission, SIGINT, did not require she go right up to the line, she could do her job from 50NM away just as easily as from 12NM. There is a slight possibility her navigation could have been off, the weather there that time of year is awful (I can testify to that personally) and LORAN (this was pre-GPS) was all that was available and it was prone to error and failure. Still, Bucher was a good sailor, and it's unlikely he would not have allowed for uncertainties in navigation. I think the N. Koreans had been stalking these ships for a long time and they saw their chance, when weather and circumstances worked in their favor and we were distracted in Viet Nam and lulled into a comfortable routine. I wouldn't doubt the same thing happened in the Persian Gulf.

I went to college with one of Pueblo's ratings, and Bucher was loved by his crew. What the Navy brass did to him was a scandal. And there is something we should all keep in mind about the military: when they have time to prepare and drill and train for a mission, they can do magic, but they also tend to get very complacent, and when faced with an unexpected situation or a bold and quick action, they often just seize up and do nothing.