Oops I clicked the wrong way!
I think this is awful. That money buys us a place in the world and soft power/influence, so it's in our best interests, for one thing.
Plus the same people who want to cut spending also tend to be against refugees and immigration. Aid spending helps develop countries so people stay put instead of leaving in search of something better.
For another, those who say 'we should spend it on our own' are also often the people who also say we should cut benefits. This money will not be spent on British worthy causes, any more than Brexit will fund the NHS.
I have worked in the aid sector as well, UK money helped desperate people out of poverty in a way that will have lasting effects. A few stories of malpractice or corruption make headlines, all the excellent work done gets no coverage.
For me, there is something really nasty and ugly about people who bleat about helping our own, charity begins at home etc. It's not either or. If the government wanted to help people in need in this country, it would. This is just a needless reduction of British influence and increase in the level of misery in the world.