It is nice to be nice but in this case actually it's important to put your own oxygen mask on before helping the next person. You think all the Aid workers don't get their jabs first? Of course they do. Because we are no use to others if we are sick, dead or dying ourselves. Once things are sorted at home we can send our forces to roll our vaccination programmes and build hospitals and all of that, but we can't expect them to do that if they or their family are sick, dead, dying, or at serious risk.
Also it is important that there are counties with high levels of vaccination because it gives us a better idea of the efficacy on a population level. Not only that but because of our over population and position (as a hub of business and travel, unable to have a hard border, etc.) then we are vulnerable, which is of course how the new strain probably developed.
I don't like it, it makes me uncomfortable to say that as British citizens my family should be vaccinated before ECV groups elsewhere, but unfortunately that is how these things always are. Do you feel guilty vaccinating your child because their are children dying of preventable illnesses in the slums of India? Do you feel guilty about feeding your child when their are children dying of starvation in sub-Saharan Africa? Do you feel guilty about your child having a safe home when their are children living in refuge camps in Syria? I feel for all those people, don't get me wrong. It must be horrendous. I will always do what I can for others, but not at the expense of me and mine. I would not give away my child's medicine, food, clothes etc, if they needed them. This is not about wants. We need to be vaccinated as a population in order for life to go back to even vaguely normal. And once it does, then we are in the right position to help others.
We are incredibly privileged in Britain to not have to live with large numbers of polio, measles, TB, Etc. Cases. That's not by accident. That's because our government and public health policies put its own citizens first. As it should. It's not about only thinking of Britain though either.
At the moment we have lots of half vaccinated elderly people, which makes me feel very anxious if we don't get at least the other half of those vaccines.