The last ministry featured in George Orwell's Nineteen Eighty-Four is the Ministry of Truth. As with the other three ministries, its purpose is the exact opposite of its title. Instead of dispensing truth, its whole purpose is to spread propaganda through the distortion of facts, disinformation and outright dishonesty.
In the US government, you can find these same principle at work in a number of ways, including the misleading names given to federal legislation. For example, the No Child Left Behind Act purposely leaves a lot of children behind! The US Patriot Act has very little to do with the subject of patriotism and almost everything to do with providing the federal government with the legal framework to spy on innocent Americans.
Remember the Helping Families Save Their Homes Act of 2009? As it turned out, it helped very few families save their homes. Almost every act in the last few years that includes the word "jobs" in it has done very little to create or protect jobs. If the word "reform" appears in the title of an act, you can be very confident that it doesn't include much substantive reform and basically maintains the status quo.
The protagonist in Orwell's story is Winston Smith. He works for the Ministry of Truth. His job is to rewrite history so that whatever current political perspective dominates at any given moment is reflected as being true, right and just in historical documents. This premise is explained in this Wikipedia entry as follows.
For example, if Big Brother makes a prediction that turns out to be wrong, the employees of the Ministry of Truth go back and rewrite the prediction so that any prediction Big Brother previously made is accurate. This is the "how" of the Ministry of Truth's existence.
The current US government is not so brazen, but you can still see shadows of it. When Barack Obama came into office, he immediately stated that his administration would neither investigate nor prosecute any criminality of the previous administration. Not only did he handle these crooks with kid gloves, but he has adopted many of their most insidious characteristics. He has turned what was once considered renegade interpretations of law into somewhat legitimized ones. What he once opposed, he now embraces.
Though the mainstream media supposedly is independent and not a branch of government, it often is difficult to discern this fact. More often than not, they serve as a megaphone for government talking points without critically examining the veracity of those very points.