In my opinion, the Bill of Rights and the freedoms enumerated therein and elsewhere are significant factors in making possible the spread of Buddha's Teaching and Practice in the USA and elsewhere in the West. I have briefly touched upon this in a number of places, including in a recent Dharma Talk "Freedom of Thought, Freedom from Thought" at
 http://prairiezen.org/Sesshin_audio.html 
and intend to clarify this further in future writings.
The following is from an interesting article about the Magna Carta and freedoms/rights:
"There was a divergence between English and American conceptions of 
Magna Carta. In the Old World, it was thought of, above all, as a 
guarantor of parliamentary supremacy; in the New World, it was already 
coming to be seen as something that stood above both Crown and 
Parliament. This difference was to have vast consequences in the 1770s.
The
 American Revolution is now remembered on both sides of the Atlantic as a
 national conflict—as, indeed, a “War of Independence.” But no one at 
the time thought of it that way—not, at any rate, until the French 
became involved in 1778. Loyalists and patriots alike saw it as a civil 
war within a single polity, a war that divided opinion every bit as much
 in Great Britain as in the colonies.
The American 
Revolutionaries weren’t rejecting their identity as Englishmen; they 
were asserting it. As they saw it, George III was violating the “ancient
 constitution” just as King John and the Stuarts had done. It was 
therefore not just their right but their duty to resist, in the words of
 the delegates to the first Continental Congress in 1774, “as Englishmen
 our ancestors in like cases have usually done.”
Nowhere, at this
 stage, do we find the slightest hint that the patriots were fighting 
for universal rights. On the contrary, they were very clear that they 
were fighting for the privileges bestowed on them by Magna Carta. The 
concept of “no taxation without representation” was not an abstract 
principle. It could be found, rather, in Article 12 of the Great 
Charter: “No scutage or aid is to be levied in our realm except by the 
common counsel of our realm.” In 1775, Massachusetts duly adopted as its
 state seal a patriot with a sword in one hand and a copy of Magna Carta
 in the other."
The full article is here:
http://www.wsj.com/articles/magna-carta-eight-centuries-of-liberty-1432912022?mod=trending_now_2