By Heather Somerville

SAN FRANCISCO, July 21 (Reuters) - Silicon Valley investor Peter Thiel, the only big-name supporter of Donald Trump from the country's technology hub, spoke on Thursday at the Republican National Convention to urge the country to discard petty cultural battles and turn its attention to solving the United States' economic decline.

Thiel offered a full-throated endorsement of Trump, echoing the Republican candidate's themes of economic decline while lambasting economic and foreign policies that have allowed the country to get embroiled in "stupid wars."

"Our nuclear bases still use floppy disks. Our newest fighter jets can't even fly in the rain," Thiel said on the final evening of the four-day convention in Cleveland.

"Instead of going to Mars, we have invaded the Middle East."

A co-founder of PayPal and an early investor in Facebook Inc who sits on that company's board of directors, Thiel is well-known for contrarian and even eccentric views: a Libertarian who supports gay rights and legalizing marijuana, and who has proposed floating cities beyond the government's reach while encouraging students to drop out of college and start companies.

His support of Trump has been both a source of curiosity and the butt of jokes in Silicon Valley, where Trump's anti-immigrant, anti-trade positions are regarded with horror. Many tech executives lean Democratic, and prominent Republican tech executives such as Hewlett Packard Enterprise Co Chief Executive Officer Meg Whitman have also rejected Trump.

Thiel, who is gay, was expected to address gay rights in front of a political party whose platform rejects gay marriage and gay rights in general. He stopped short of such an appeal, however, addressing his sexuality only when saying: "I am proud to be gay. I am proud to be a Republican. But most of all, I am proud to be an American."

He is only the second openly gay man to address the Republican National Convention, CNN reported.

"When I was a kid, the great debate was about how to defeat the Soviet Union, and we won," Thiel said. "Now we are told that the great debate is about who gets to use which bathroom. This is a distraction from our real problems. Who cares?"

Thiel said his support for Trump was based on the belief that the candidate could address the country's economic decline. He cited the space program and other government technology achievements as examples of what has been lost.

Thiel drew parallels between himself and Trump each as a "builder."

His family emigrated from Germany when Thiel was one year old, and arrived in Cleveland - the city hosting this week's convention. When Thiel pointed that out, he got loud applause.