It would be a serious strategic error for President Bush to allow such affronts to American sovereignty to go unchallenged.

CENTERFORSECURITYPOLICY: us_wants_saddam

I'm afraid I can't let some extreme and unfounded comments go unchallenged.

BBC: Is Marion Jones right to drop coach?

"In no instance is this going to go unchallenged, " says William Kovacs, the Chamber's senior vice president for environment, technology and regulatory affairs.

FORBES: Climate

There has been a healthy academic debate over the world's longest river for some years and the claim from Brazil may not go unchallenged.

BBC: NEWS | Americas | Amazon river 'longer than Nile'

Mr Haass, who left the province to return to Washington on Wednesday afternoon, said the US Government would not let the actions of the terrorists go unchallenged.

BBC: Assembly recall to discuss attacks

Too many witnesses go unchallenged, too many arguments remain unpacked.

BBC: One last, lingering look behind

This blatant disregard for the law must not go unchallenged.

FORBES: Gary Johnson to Obama: 'Time's Up in Libya'

The bottom line is that a distressed debtor cannot just presume that all charitable giving will go unchallenged, and therefore it is best to plan well in advance for charitable giving and taking into considerations such things as an unforeseen financial crisis.

FORBES: McGough: Debtors' Charitable Giving Limited To 15% Of Gross Income In Bankruptcy

Dettori came through on the outside with 300 meters to go and came home unchallenged from 6-1 shot Eagle Mountain, the mount of Johnny Murtagh and one of eight runners for Irish trainer Aidan O'Brien.

CNN: Dettori triumphs in Derby at last