> USA beat the UK for importing slaves by a few weeks
Do not pretend for a moment that USA was leading on anything here.
1. UK had already abolished importation of slaves. No-one could be a slave in the UK since 1778 (Scotland, Eng\Wales was earlier). If you "imported" a slave to the UK, they would become free.
2. The ~1807 US/UK laws were far from equivalent - the UK act was abolishing the trade completely. The US was only ending importation. Domestic / inter-state trade was unaffected.
3. The US law came into effect 6 months after the UK one.
The day Jefferson passed that 1807 act, his 100s of slaves got a little more valuable. Who needs imports when you can abuse 16 year old enslaved girls? As he signed this act, he was, yet again, impregnating Sally Hemings so that in 1808, his 7th bastard child born was into slavery. The birth was recorded in the Farm Book alongside other livestock.