error in XHTML v1 page

There appears to be a problem with the XHTML1-strict.dtd file, I clicked on it and got an XML error message, reproduced below. Could this be why my first attempt at a strict XHTML1 page has resulted in displaying the XHTML file as Internet Explorer (5.5) would display an XML page?

The page is at http://www.tonyhedges.co.uk/politics.xhtml

Tony Hedges

below is what is displayed in IE5.5 when you click on Strict DTD in the XHTML1.0 page.
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The XML page cannot be displayed 
Cannot view XML input using style sheet. Please correct the error and then click the Refresh button, or try again later. 


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Cannot have a DTD declaration outside of a DTD. Line 26, Position 12 

<!ENTITY % HTMLlat1 PUBLIC
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