Future Planning RE aquiring citizenship by living in Saipan

[JE57 239]

Hello,

   Currently my wife and I live abroad and have no plans to move or live in the USA in the near future.   However,  as I look into the future at retirement for myself I'm thinking how she can obtain US citizenship so that she can enjoy the many benefits of such citizenship but specifically the ability to travel on a US passport and avail of my social security benefits should I pass away untimely.   At the moment we are not really interested in leaving SE Asia and don't see that changing in the future.  As such, in retirement is obtaining a spousal visa, moving to Saipan setting up a home and life there for 3 years make my wife eligible for naturalization.   If so can does she have to maintain physical presence in Saipan for 3 years or are we free to travel periodically as long as we spend more time in Saipan (USA) than out of (USA)?    Any thoughts about the viability of this plan would be appreciated.   We see Saipan as a good option as we assume prices, climate, access to SE Asia destinations not the least of which is the Philippines would be much better than Mainland USA.     Thanks in advance.