ויקחו את לוט, They took Lot, etc. The reason the Torah adds that Lot was Abraham's nephew and that he lived in Sodom, something we have known for a long time, is to tell us that these kings were very well aware of who Lot was. This did not deter them from taking Lot captive. The Torah stresses that these kings deliberately ignored the fact that they were provoking a man of international repute when they took his nephew into captivity. None of this would have happened to Lot had he not chosen to live in Sodom. The matter can be compared to Israel capturing a substantial part of Moab though G'd had forbidden Israel to provoke war with Moab or to attack it (Deut. 2,9). Once the Emorite king Sichon had defeated Moab in war, the lands captured by Sichon were no longer considered as Moabite territory, and Israel took possession of them. Here too, once Lot had chosen to throw in his lot with the Sodomites he was no longer considered as part of Abraham's entourage, and was not entitled to the protection Abraham could have afforded him. This also explains why Abraham did not try to secure Lot's release by peaceful means. He knew that the 4 kings knew very well whom they had taken prisoner. If Lot's relationship with Abraham had not stopped them, there was no point for Abraham to warn those kings before attacking them. Lot's capture was a hostile act against Abraham.