What's behind Germany's transport strikes that have stranded air, rail and bus travelers?

Thousands of travelers across Germany have found themselves stranded after ground staff walked off the job at seven of the country’s biggest airports. The one-day strike by the Ver.di labor union runs until Wednesday morning and affects several hundred flights at Lufthansa’s main hubs in Frankfurt and Munich as well as airports in Berlin, Duesseldorf, Hamburg, Cologne-Bonn and Stuttgart. Germany's rail and local transport sectors also have seen strikes this year. Unions want higher wages and better working conditions amid inflation and staff shortages. But travelers and commuters are frustrated as Europe’s economic powerhouse could see more strikes ahead.