Why don't Christians claim every invention to be invented in the west to be a Christian invention like Muslims?

Thats because Christianity restricted inventions in the world. This is why science destroyed Christianity and many left that religion because it didn't have the truth.

Harun Rashid sent a clock to french ruler who couldn't work out it worked so he said it had a devil in it that made it work!
This was in the 9th century.

Algebra is an Arabic word which means to compel, Jabr is the arabic word.

The zero was invented by the Muslims and the whole numbering system is another legacy of Islam. Can the west survive if they use the roman numeral system again? Impossible. Your computer uses algebra, would you be without your computer?

Please see this video from Muslim heritage website by Doctor George Saliba who will explain this legacy. I dare you to watch it!
http://muslimheritage.com/topics/default.cfm?ArticleID=693

Astronomy including names of Arabic origin
http://muslimheritage.com/topics/default.cfm?ArticleID=833

What is Islam did for us? Review of the book by Tim Wallace-Murphy - A Christan historian!!
http://muslimheritage.com/topics/default.cfm?ArticleID=811

1001 Muslim inventions
http://www.1001inventions.com/index.cfm?fuseaction=main.viewSection&intSectionID=309