Jamieson, Fausset and Brown on 1 Kings 16:2

2. Forasmuch as I exalted thee--The doom he pronounced on Baasha was exactly the same as denounced against Jeroboam and his posterity. Though he had waded through slaughter to his throne, he owed his elevation to the appointment or permission of Him "by whom kings reign."

over my people Israel--With all their errors and lapses into idolatry, they were not wholly abandoned by God. He still showed His interest in them by sending prophets and working miracles in their favor, and possessed a multitude of faithful worshippers in the kingdom of Israel.