Summary: Thursday on the NewsHour, an overheated wheel bearing and a warning that came too late, government investigators explore possible causes of the train derailment that led to a toxic chemical spill in Ohio. Ukraine's fight against Russia forges new levels of unity and resolve as the war approaches the one-year mark. Plus, abortion pills become the latest battleground over reproductive rights. PBS NewsHour is supported by - https://www.pbs.org/newshour/about/funders
