As you know, anybody can sue anybody for anything. Whether they will recover is an entirely different matter.
The four elements of the tort of negligence are duty, breach, causation (injury), and damages. Without a duty, there is no negligence. Generally the government does not owe a duty to individuals, absent some special relationship or specific promise of protection. Thus, the government does not generally owe you a duty to protect you, unless it has promised protection, or in some other way established a duty to protect.
In addition, the Federal Tort Claims Act (FTCA) provides the federal government with limited waiver of sovereign immunity, but there are exemptions, including "discretionary functions," which is very broad. Thus, government is often immune from liability while private persons would not be.
Quote:(a) Any claim based upon an act or omission of an employee of the Government, exercising due care, in the execution of a statute or regulation, whether or not such statute or regulation be valid, or based upon the exercise or performance or the failure to exercise or perform a discretionary function or duty on the part of a federal agency or an employee of the Government, whether or not the discretion involved be abused.
If the government exercises its discretion and fails to give the warning, the above exemption would arguably apply to insulate the government from liability. States have similar Tort Claims Acts.