[TexasGator]

“but the Guamanians still view the Saipanese as collaborators who are not their equals.”

Guam was not occupied by the Japanese. In 1943, Saipan had a civilian population of 29,348 Japanese settlers and 3,926 Chamorro and Caroline Islanders and by 1944 there were over 30,000 Japanese military in Saipan. Basically, they were not collaborators, they were Japanese.

[Enterprise]

"Guam was not occupied by the Japanese."

Strange, the U.S. Military killed 18,000 Japanese non-occupiers.

"In July 1944, US forces retook the island of Guam after weeks of fierce fighting, leading to over 7,000 American casualties and over 18,000 Japanese killed."

Battle of Guam

[Vigilanteman]

Your point is well taken, but when the war ended, the Chamorro and Caroline Islanders remained on Saipan; the Japanese did not. The United States took control of the island (and not just Saipan but smaller islands around it) and proposed that they have territorial status equal to Guam or American Samoa.

The Guamanians objected. This is why Guam retains a special territorial status today. Saipan, Tinian, Rota and the other 12 uninhabited islands form the Northern Mariana Island Commonwealth (NMIC) and Guam, alone, the southernmost of the Mariana Islands retains territorial status.

Some say this is now actually a disadvantage for Guam since, as a territory, they have hope of achieving statehood whereas a commonwealth such as Puerto Rico or the NMIC could choose either statehood or independence.

As a practical matter, however, it means little since either commonwealth or territory residents enjoy almost all of the advantages of U.S. citizenship without the taxing obligations.