Is dual citizenship possible without living in US?

I am living in the UK with my British husband.  I am American.  I plan to apply for UK citizenship in 5 years.  I was wondering if it is possible for my husband to apply for US citizenship without our residing in the US.

We would both like to have dual citizenship as it would probably make travel between the two countries simpler.

Thanks,

Nancy

I was wondering if it is possible for my husband to apply for US citizenship without our residing in the US.

No. He absolutely has to reside in the US for at least three years as a permanent resident before he is eligible to apply for US citizenship.

(and as a side note- any particular reason you're waiting 5 years to apply for UK citizenship?  Spouses of UK citizens only need three years of residence + ILR to qualify for naturalisation.)

I thought I needed to wait for 3 years after the ILR before I could apply for citizenship.  I appreciate your clarification on this, also on the citizenship question for my husband.

Many thanks,

Nancy

I thought I needed to wait for 3 years after the ILR before I could apply for citizenship.

That's incorrect.  A spouse of a British citizen needs only to reside in the UK for 3 years (with not more than 270 days out of the country in that time) and be an ILR holder to qualify for UK citizenship.  You don't need to have held ILR for any specific amount of time, because spouses (and civil partners) of British citizens are exempt from that sort of rule.