JERUSALEM — The arrest of three Bedouin recruited into the Islamic Hamas organization has thrown into sharp relief the changes undergoing these descendents of Arabic-speaking desert nomads. Does it represent a dangerous Palestinization of the Bedouin? Or are these exceptions to the fact that most of the Israeli Bedouin are reasonably loyal citizens of the state?

Traditionally, the Bedouin once cherished only one kind of loyalty — to their own tribe. Their Islam was flexible because of their way of life. Bedouin were traditionally devout but never practiced orthodox Islam. The Bedouin tended to be more neutral than their Israeli Arab brethren. They served in the army. But a growing Islamization process has eroded the tolerance that they once showed and today there are a lot more Islamic components in their character.

While only half as many Bedouin live in the north than in the Negev, they make up about 70 percent of those volunteering for Israeli army service. But the north-south split is deeper than this and it was no coincidence that the alleged Hamas recruits came from the poorer and swelling communities of the Negev.

Once, 20 years ago, the Bedouin were caught between their ancient nomadic ways and Israel's need for land for the army, for urban development, for settlements. But today, they are much less nomadic and more likely to be living in semi-permanent tin shacks or cinderblock homes, the impoverished sons and daughters of truck drivers, construction workers and night guards than proud desert shepherds.

The once open deserts around Beersheva are today smothered with shantytowns of tin and plastic sheeting as the new generation of Bedouin set up their homes.

Demographically, the Bedouin are mushrooming. About half of the Negev Bedouin live in seven planned towns. The rest are scattered in the desert and refuse to be resettled in which started out, and remain, instant slums.

Terribly neglected and grossly undereducated, the communities have had to import teachers from the Galilee and the Triangle. This coupled with mass communication has provided them with political awareness, national sentiments and made the young in particular more radically Islamic. Also, demographics have in general led them to identify more with the Palestinians than even with Israeli Arabs.

More and more Negev Bedouin are marrying Palestinians from the West Bank and Gaza Strip. Coupled with the end of their sedentary lifestyle, and strengthening Islamization, the Negev Bedouin appear to be quickly losing their identity and undergoing a process of Palestinization.