Your having a laugh.
We sold our steelworks to China and they closed them down.
How do we make weapons to defend ourselves.
I don't mean to be a gloom munger but the UK isn't exactly in a strong position to defend itself.
Useless info after WW1 was finished the forestry commission was set up as the UK almost ran out of wood.
We import so much stuff, including essentials like clothing and food, an international war would be a disaster for the UK.