Explain the difference, then.
"Intelligent design" is the belief that design is evident in the universe. The most commonly cited "evidence" of this design is "life is so complicated that it couldn't have arisen without a designer."
"Creationism" is the belief that life did not evolve, but was created, as is, or at least very like as it is today.
So, Michael Behe believes that once upon a time, there were single celled organisms. They mutated and formed colonies. Those mutated and formed plants and animals. Those kept mutating and having descendants that were very much, but not exactly, like their parents, until one of them looked an awful lot like us, and at that point, God said he was done and called that one "Adam".
The difference between Behe and us is that he thinks those mutations were no accident. He thinks God made those mutations happen. Furthermore, he thinks that the mutations were so improbable that they couldn't have happened without divine intervention.
One of the reasons for the confusion is, indeed, that book "Of Pandas and People". They wrote a book about creationism, and then changed the word creationism to "Intelligent Design", but described it just as they had described creationism. Reading that book, a lot of people said, "Now just a gol darned minute. We believe in intelligent design, but we don't believe all that stuff about creating fish with fins. We just believe it couldn't have happened without God."
Over time, the different camps have been clarified, so that Michael Behe, and people like him, say that they are not creationists, because they don't believe that organisms were "created", as in "created from nothing". They believe that organisms were formed through divinely guided evolution.
Now, if you absolutely insist on calling Behe and his ilk "creationists", neither I nor they can stop you, but they don't call themselves by that term, and there is a significant difference between the beliefs of those who do not call themselves creationists, and those who do.