Without the Pulaski, the Continental Army headed by George Washington would have been not much more than a very determined and fairly large militia. There were virtually no professional soldiers in the Thirteen Colonies other than British Units, who obviously would oppose revolution against the English Crown. So, yeah, Pulaski's input was vital – he trained the men and even used some of his own finances to do so. "The Father of the American Cavalry" is an unofficial title given to him by American historians. So make of that what you will.
Also, with Thaddeus Kosciuszko (as he is known in the US) the Continental Army would have no military engineer. Kosciuszko fortified Philadelphia harbor (then the main harbor) and build several key forts including West Point, which now serves as the US Army's Officers' School and there is a "Kosciuszko Garden" there.
It's a great irony of history, but as Poland fell into darkness and off the map, Poles helped create another nation, which today is know as the United States. The Polish Constitution of May 3rd is also based on the US Constitution. Kosciuszko was good friends with Thomas Jefferson. If you look at Jefferson's official portrait, he is wearing a Russian winter coat, the one Kosciuszko gave him! I'll post more on Kosciuszko soon.