1.   But historically, the failure to inject substantial and timely aid has only hardened ethnic divisions.

2.   But the white flight has hardened a division in Matteson.

3.   The conflict is hardening ethnic divisions, causing worry that it could cause Bosnian Serbs to try to secede from the country and join Yugoslavia.

4.   The Estrada corruption allegations led to an unprecedented impeachment trial, which hardened political divisions even as it enthralled the nation on live television.