Recent posts hidden from frontend

This has really got me puzzled. Three days ago all of the posts from the last four years stopping being visible on the frontend. Originally it looked like just the posts from when I switched from blogger to wordpress were gone (from March 2006) but now I can’t see any of my posts from mid-2003 on. They’re in the backend. Indeed, I can view them from the backend when I hit view. But on the front of the site the latest post is from 2003.