Judean and Syrian

I am reading through Stern's GLAJJ and I am intrigued by relationship between Ioudaioi and Syrioi. Consider the following:

a. "The Phoenicians and the Syrians of Palestine acknowledge of themselves that they learnt the custom [of circumision] from the Egyptians, and the Syrians of the valleys of the Thermodon and the Parthenius, as well as their neighbours the Macrones, say that they learnt it lately from the Colchians." Herodotus, Hist. 2.104.3.

b. "And indeed, says, Theophrastus, the Syrians, of whom the Jews constitute a part, also now sacrifice live victims according to their old model of sacrifice". (Theophrastus cited in Porphyry, On Abstinence, 2.26.

c. "All the opinions expressed by the ancients about nature are found also among the philosophers outside of Greece, some among the Indian Brahmans and others in Syria among those called Jews". Megasthenes cited in Clement of Alexandria, Stromata 1.15.72.5.

d. "The philosophers, they say, are in India called Calani, in Syria by the territorial name of Jews; for the distrinct which they inhabit is known as Judaea. Their city has a remarkably odd name: they call it Hierusaleme." Clearchus of Soli cited in Josephus, Apion 1.179.

What does this mean for the debate about connecting Ioudaioi with Judea? Should we connect it also with Syria in some way as well? Or does this link of Syrians with Judeans stem from a European ignorance of the complexity of near eastern ethnic groups?