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USA Will Invest in High-Speed Train to Fight Climate Change
(www.raillynews.com)
This is a most excellent place for technology news and articles.
Too expensive and hard to maintain. You can get pretty good speeds with traditional rail, in western Europe there are trains reaching 200-250km/h.
300-350km/h actually. Although most places indeed average 200-250 on high speed lines, for example in Germany because those services often share infrastructure with slower trains. In France and Spain, however, infrastructure is often exclusively high speed which allows much higher sustained speeds around the 300km/h mark.