As a theory, yes. As an attitude, apparently not.
Behe's concept of "irreducible complexity" centered around the idea that there are some structures that are so complex that they no longer function when one component is removed (thereby making a stepwise construction through evolution grotesquely improbable). His favorite example was the bacterial flagellum.
Behe's hypothesis was put to the test, and failed utterly. Researchers like Ken Miller later showed that the flagellum can, in fact, be built from more primitive precursors (in this instance, the type 3 secretory system that bacteria use to inject toxins into other cells).
Behe was unperturbed, and in the Dover trial rewrote his thesis so that an irreducibly complex structure cannot retain its
current function when one component is removed. While this definition certainly entails that the bacterial flagellum is irreducibly complex, it's meaningless since evolutionary processes can account for its development, regardless of its "irreducibly complex" nature.
This is where ID as an attitude is unfalsifiable. Behe is stubborn and adamant that his thesis is true, and will bend over backwards to make sure it is so by ignoring all other relevant data.