Chinese tech giant Huawei has sued the U.S. government, arguing that legislation Congress passed last year that restricts its business in the United States is "unconstitutional." The case, which analysts see more as a public relations move, is but the latest in an intensifying effort by the telecommunications company to fight U.S.security concerns, which Huawei argues are unfair and unfounded.In its lawsuit, Huawei argues that Section 889 of the National Defense Authorization Act violates the constitutional principles of separation of powers and due process. By singling out the company and punishing it without a trial, the company also argues that the law violates the Constitution's bill of attainder clause. Section 889 bans federal agencies and their contractors from purchasing equipment and services from Huawei as well as another Chinese telecom company ZTE. It was signed into law last year by President Donald Trump."This ban is not only unlawful but also harms both Huawei and U.S. consumers," Huawei's rotating chairman, Guo Ping, told reporters at news conference in Shenzhen on Thursday. "This section strips Huawei of its due process, violating the separation of powers principles, breaks U.S. legal traditions, and goes against the very nature of the constitution."Guo said that Huawei was left with no choice but to take legal action, noting that neither lawmakers nor the government had shown any proof to date to back up concerns the company is a security concern.Huawei's chief legal officer, Song Liuping, added that the clause gives it no recourse to defend itself or clear its name."Section 889 is based on numerous false, unproven, and untested propositions. Contrary to the statutes' premise, Huawei is not owned, controlled, or influenced by the Chinese government," Song said.That, however, is a central point of the debate over Huawei: how much a security threat the company is? And is it really independent from China's authoritarian government?That debate is heating up at a crucial time as countries across the globe are preparing to roll out next generation mobile communications networks or 5G, an area where Huawei is a global leader. At the press conference, Huawei officials argued repeatedly that the ban would cut off Americans from its advanced technology. They also gave assurances again that the company would never install backdoors into their equipment and that it puts the security concerns of its customers first.Some countries such as the United States, Australia and New Zealand believe the company is a security threat and have already banned Huawei from their roll out of next generation mobile communications networks.Others, including Britain, Canada and Germany, are still weighing a decision. At the same time, Huawei chief financial officer Meng Wanzhouis facing extradition to the United States from Canada over violations of U.S. sanctions on Iran.With Huawei fighting a battle on multiple fronts, the lawsuit is as much about public relations as it is an effort to clear itself of accusations that it is a security threat.Legal analysts said it is unlikely the case will even go to trial."As a PR matter, this is brilliant, the fact that we are just talking about this now, tells you this is a great PR move, as a legal matter, this is a reach, to put it charitably," said David Law, a professor of political science and law at Washington University in St. Louis and law at the University of Hong Kong. "I just can't see how a federal district judge in Texas is going to let this go to trial much less hand Huawei a win."The case could put more pressure on the U.S. government to disclose more evidence to support its claims about the security threat the company poses, according to some legal analysts. That could help Huawei in the process, said Calvin Yang, director of the Taiwan Bar Association's intellectual property commission."I think this is a move that carries more political weight than any litigation significance," Yang said, adding that the company's case was more about challenging the legitimacy of U.S. accusations. "It's using judicial procedure to force the federal government to provide more evidence to support its allegations of so-called backdoors in Huawei's equipment." Some legal analysts have noted that Huawei's case is similar to the legal battle Russian cybersecurity firm Kaspersky lost late last year. Kaspersky challenged a ban on the use of its software on U.S. government networks, but last November, a federal appeals court ruled in favor of the federal government.Whether that will figure into the case is too early to tell, and that is if it goes to trial, legal analysts note.When it comes to national security concerns, they add that courts are unlikely to probe too deeply into those questions.