Oren Dorell

USA TODAY

The Senate approved new sanctions Wednesday against North Korea to make it harder for the reclusive nation to access funds to develop long-range missiles and nuclear warheads. The House passed a similar measure last month.

Yet any sanctions Congress imposes are unlikely to deter North Korea, which fired a long-range rocket on Sunday and conducted a nuclear test last month in violation of U.N. resolutions. The reason sanctions are ineffective: China.

China is the financier: Most banks that North Korea uses to finance trade, imports and weapons programs work through China, said Richard Fisher, vice president of the International Assessment and Strategy Center.

“The financial wherewithal for North Korea to sustain itself runs through China,” Fisher said. “Without China participating, financial sanctions will not have a decisive effect.”

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Chinese companies are fronts for North Korea: Unlike U.S. sanctions on Iran, which were partially lifted recently in return for limits to that country's nuclear program, the proposed sanctions on North Korea do not target companies of third countries that do business in North Korea.

"That's partly because it's more difficult to discover those (companies)," said George Lopez, a professor at the University of Notre Dame's Kroc Institute for International Peace Studies.

Lopez said foreign companies often think they're doing business with legitimate Chinese companies, only to find they were actually fronts for North Korea. Sanctions against Chinese companies that do business with North Korea is too risky for U.S. businesses that seek to penetrate the mammoth Chinese economy, he said.

"For the benefit of targeting a few companies, most people in the State Department would say it's not worth it," Lopez said.

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China abets North Korea: China is complicit in much of what North Korea does, Fisher said.

Chinese President Xi Jinping allowed a Chinese company in 2011 to provide North Korea with 16-wheel trucks, which are now used to transport inter-continental ballistic missiles that the U.S. Defense Department says could carry a nuclear payload as far as Seattle.

“When North Korea and Iran seek to purchase high technology, materials or equipment for their nuclear and missile programs, the place that they like to shop is China,” Thomas Countryman, assistant secretary of State for international security and nonproliferation, told reporters in January.

China has a high-technology economy and produces a number of advanced goods that would benefit such programs, Countryman said. China should “exercise the same degree of vigilance and control on strategic trade with Iran and North Korea as other countries do,” he said.

China props up North Korea's leadership: China wants the North Korean leadership to survive, whatever it takes.

China uses North Korea to influence the democratic government of South Korea and to pressure Japan, Fisher said.

“It views the regime in Pyongyang as a brother Communist system that must survive at all costs in order to prove to the world that China is not the last Communist regime on the planet,” Fisher said.