Historically, people of Poland and other countries of Eastern Europe (Czech Republic, Hungary, Slovakia, Baltic Republic etc) had always very friendly attitude towards the USA.
There are many reasons:
The massive immigration at the end of XIX century took place from Eastern Europe to America. You can read more about it in a series of articles about History of Polish Immigration. People from Eastern Europe believed that it was very easy to get rich in America, that this is a dream place to be in - especially compared to the place where they lived. One of the first massive Eastern European immigration originated from poor, mountainous regions of South Poland and Slovakia, America for them was a dream country, a country of potential prosperity. Since this immigration happened not a long time ago (the end of XIX century) many Americans of Eastern European origin are keeping in touch with their country of origin and their families in Poland. Polish Americans can usually trace their families in Poland, they identigy themselves as Polish Americans, whereas Americans from earlier immigration often cannot identify their roots properly in censuses calling themselves just Americans.
When Poland underwent an economical crisis in 80-es and the value of dollar was especially high they were helping out not only their direct families. Polonia (people of Polish origin living abroad) were helping in building several hospitals. They also donated lots of medical equipment.
There is some historical entanglement between a fate of Poland and a fate of the USA. Just when Poland lost its independence America became a free country.
When Poland lost independence at the end of XVIII century in three partitions - Polish patriots, between them Kazimierz Pulaski and Tadeusz Kosciuszko left to America to fight for American independence. For Poles the value of freedom is as precious as for Americans. This is not necessary a case in every society and nation where other virtues have higher values. Both, Poles and Americans share a common devotion to the cause of liberty, freedom and democracy. We never had a tradition of strong central power like Russia or Germany did. Polish kings' power was always limited, they were controlled by parliament. Unfortunately it did not necessary had good consequences for Polish state which was weakened by inefficient parliament like liberum veto - one member of parliament could block the whole resolution. When Poland was in danger of losing independence - Poles established a progressive constitution. Poland's constitution was the second democratic constitution in the world (May 3rd, 1791). Polish constitution act gives rights to common people but it came too late to protect Polish independence.
A couple of years ago certain political joke was circulating in Poland. According to this joke, Poles would like to detach from Europe and become the 51st American state.
There is some true in this joke. It was mentioned, with sarcasm by one of the Polish political journalists (Krzysztof Wojna) after martial law was imposed. For the last forty years after the WW II Eastern Europeans were under the influence of Soviet Union. Soviet system was imposed from the outside, it was totalitarian and non-democratic. It did not have any understanding of local traditions and culture. Soviet Union was controlling all the satellite countries and was keeping its military there. Poland was the least loyal and obedient Soviet satellite, maybe because it was the biggest, maybe because people in Poland were used to foreign occupants and they knew how to resist it.
The USA was seen as a powerful country that could oppose Soviet policy and bring freedom and wealth to EE. Eastern European countries never had stationed American military forces on their territory as Western Europeans did. This caused some tension among the USA and its Western allies. We had Soviet troops, whether we wanted or not. Some of them, especially their commanders behaved as like they could do whatever they wanted without any respect to an indigenous population and Polish local and central government. The USA was seen in Eastern Europe as free, rich and democratic country that does not impose its laws on others. This might change since the USA is the only superpower in the world and is acting sometimes without seeking a consensus with other countries.
The question arises, does America love Poland the same way Poland and Poles love America?
This book was an object of several commentaries in the press. The author was invited to many political discussions. It is really interesting! Of Paradise and Power: America Vs. Europe in the New World Order by Robert Kagan.