(CNN) -- The United States and Germany are sending Patriot missiles and troops to the Turkish border, a warning to Syria's besieged President Bashar al-Assad. The surface-to-air interceptors would be "dealing with threats that come out of Syria," said U.S. Defense Secretary Leon Panetta. Threats would include Syrian strikes inside Turkey and fighting between the government and rebels that extends into Turkey. Errant Syrian artillery shells struck the Turkish border town of Akcakale and killed five Turkish civilians in October. "We can't spend a lot of time worrying about whether that pisses off Syria," said Panetta after signing the order Friday. He spoke after arriving Friday at Turkey's Incirlik Air Base, a U.S. Air Force installation about 80 miles from Syria's border.
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NEW: German parliament OKs deployment of German Patriot anti-aircraft missiles to Turkey
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U.S. Defense Secretary Leon Panetta signs order for missiles and troops en route to Turkey
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The U.S. military will send 400 personnel and two missile batteries to Turkey
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Move signals U.S. support for Turkey in the face of possible threats from Syria
A second official said @placeholder and his commanders appear to be fully aware the opposition has made significant military gains in recent weeks and that al-Assad "is not out of it" in his understanding of the current situation.