I didn't want to hijack Sapient's thread on buying American since I have nothing to say on the topic other than buy whatever you want. I did want to address a few things chazmuze said though. 

Except it doesn't. On the subject of money the Constitution only gives Congress the power to "coin Money, regulate the Value thereof, and of foreign Coin, and fix the Standard of Weights and Measures;" in Article 1 Section 8 and Article 1 Section 10 which I assume you are referring to is a prohibition on the states. 

Obviously, this clause does not apply to the federal government at all. 

First of all counterfeiting gold and silver used to happen all the time. People don't often counterfeit quarters because they are not valuable enough to bother, although counterfeiting of rare gold coins is not uncommon even today. 

As far as what the government can do, you really need to study a little monetary history during the gold standard. The government has the explicit power to regulate the value of money and even under the gold standard the government could inflate money at will, albeit with less precision than today. Your apparent belief that switching back to the gold standard is somehow going to prevent the government from borrowing money or inflating money has no basis. There are many games that can be played with gold backed money. I also fail to see how changing our monetary standard would have any relation to what sort of tax system our government uses. VAT taxes and corporate taxes can be levied under any monetary standard.

Also, it is important to note that every other major country is also based on fiat money which brings about the largest problem with using gold- where do we get enough gold? At current market prices our existing money supply is significantly larger than the entire gold supply in the world, let alone compared to the gold our government could get their hands on however tyrannical they became at seizing it. The result would be massive inflation in the value of gold and massive deflation in the value of the dollar overnight. 

What would be particularly devastating to our economy is that gold and silver are no longer luxury metals. They are now used in a variety of modern applications such as being used in the computer you are on right now. There is simply no reason for us to cause that kind of run on the gold and silver markets simply so we can be happy saying we are on the gold standard. Ultimately, the value of any currency is only valuable if people believe it has value and are willing to use it as a method to indirectly exchange labor. It doesn't matter whether it is based in gold, silver, copper, sea shells, fur or fiat- its sole value is whether you are willing to take the currency in exchange for whatever labor you produce and whether I am willing to accept it in return from you or someone else in exchange for my labor. 

The benefit of fiat money is that it does not require storing a physical asset which allows it to be much more elastic- which is a very good thing. I agree that our current government is completely abusing that power and fiat money being more elastic the negative effects of abusing it are slower in coming than if similar things were done with gold. However, it is a mistake to confuse the abuses of our government and blame it on fiat currency and throw the baby out with the bath water. Our government abuses pretty much all of its powers right now imo including police power, military power, spending power and taxation power. It would be irrational to come to the conclusion that because it is abusing those powers we should not have police, military, taxes or spending. Although, there is no doubt that the government should be reigned in, in all of these areas. 

If you are interested in the topic I did a blog on it a while back as part of a larger series and any intelligent feedback, argument or discussion is welcome. 

http://www.rationalresponders.com/g_s_or_bi