1. The present-day descendants were not themselves slaves.
2. Neither I nor any of my ancestors were ever slave owners.
3. Even if my ancestors had been slave-owners, they were individuals and I am a different individual. I accept no responsibility whatever for anything they may or may not have done because it was not something over which I had any control or even the slightest influence.
4. If you start down that path of compensation for historical events, where are you going to stop? Should the French pay compensation for the depredations of Napoleon's armies? Should we in England claim compensation from Normandy, Saxony, Scandinavia and Rome?