The Fed can influence the money supply in any way it pleases through the FOMC
I understand it. And one of the ways of doing so is to change interest rate.
No, you’ve got the cause and effect reversed. The Fed performs open market operations, and that has an effect on the various (short and long-term) interest rates. But the point is that it has a more direct effect on the money supply.
People tend to speak of interest rates and the money supply as if they were one variable, when in fact it is important to distinguish short-term interest rates from long-term interest rates, cash from interest-bearing instruments, as well as a Fed rate cut from a money supply expansion.
Secondly I would like to know why do you think that people should prefer to spend money quicklier when interest rates are high. In my opinion they just don´t want to have them cash and they rather have them deposited in bank because it yields some money due to interest rate.
I would recommend that you re-read my post.
I said “spending it, either through investment or consumption.” “Some people will buy CODs and Treasury Bills ; others will buy shoes and necklaces…” What happens when you invest your money into a Certificate of Deposit? Someone else gets your money. And he doesn’t get it because he wants to sit around and do nothing and repay the money with interest 6 months later; he wants to spend it on something!
As I have said on other threads, a penny saved is a penny spent by someone else. So, as far as the effects on the velocity of money are concerned, it does not matter whether you convert your cash into a necklace at the shopping mall or into a COD at your bank: in either case, higher interest rates encourage you to perform such conversion sooner rather than later, and the conversion will contribute to the velocity of money.
Thirdly I had a look in some book and there was written that V doesn´t change in short term.
V has probably been the most mysterious and un-understood of all variables in twentieth-century economics. Some economists think that V is relatively constant; others say that V/Q is constant; and there could easily be some who think that V reflects the influence of God. 
My opinion is that, since the short-term interest rate is the cost of holding money in your hand, it is quite reasonable to conclude that higher short-term interest rates will make people more eager to minimize the time money spends in their hands. You may think of money as a potato being passed around among people, with the short-term interest rate being its temperature. The hotter the potato, the faster it will change hands!
It´s interesting. Why do you want to become American? Don´t you find other countries better?
Well, as far as taxation is concerned, Seychelles is quite definitely better, and people are more polite and civil in England, and more receptive to well-meant criticism in Israel–but if you look at the overall picture, I think America has no competitor.
I don´t know much about situation in other countries but what I don´t like about America is many stupid laws they have enacted recently
Can you give a couple of examples?
and rate of people believing in god.
There are certainly more people believing in God in America, but most of them don’t want to force their religion on other people (unlike in Europe!) Also, America is very Calvinistic while Europe is terribly Lutheran–and this applies to the Catholics too!
Plus, what really matters is not whether a person believes in God but whether he is guided by an irrational philosophy. I don’t have any statistics on the rate of people believing in environmentalism in America vs. Europe, but I have a strong suspicion on where the rate might be higher.
What is the situation in Hungary? As far as I know you had communist party in government few years ago. Is it still true?
Yes, the Socialist Party. They were re-elected this spring. And I’m actually glad they won because the other big party is even worse. The party of the late Prime Minister Antall, who governed from 1990 to 1993 and was one of the very few principled politicians I have seen in my lifetime, got only 5% of the popular vote.
The new Socialist government is doing what I described in step 3 above: raising taxes and interest rates.
BTW, I’m planning to leave Hungary this September. 