以下引述一段 Thomas Jefferson (美國第3任總統) 寫給 James Madison (美國第4任總統、人稱「美國憲法之父」) 的信。
"On similar ground it may be proved that no society can make a perpetual constitution, or even a perpetual law. The earth belongs always to the living generation...... Every constitution then, and every law, naturally expires at the end of 19 years. If it be enforced longer, it is an act of force, and not of right.--It may be said that the succeeding generation exercising in fact the power of repeal, this leaves them as free as if the constitution or law has been expressly limited to 19 years only."
--- letter from Thomas Jefferson to James Madison, 6 Sept 1789.
事實是，美國憲法未等到19年就已經作出多項修訂。美國憲法於1789年生效，至今有過27項修訂，當中12項是在首15年內進行，大都是在憲法主要撰寫人、「憲法之父」 Madison 引導下進行。為何自己寫的憲法都要改？為何要違反立法原意？為何要今日的我打倒昨日的我？因為實行後發現憲法有漏洞嘛，跟不上實際情況就當然要改的啦！
1st-10th December 15, 1791
Bill of Rights
11th February 7, 1795
Makes states immune from suits from out-of-state citizens and foreigners not living within the state
12th June 15, 1804
Revises presidential election procedures
13th December 6, 1865
14th July 9, 1868
Defines citizenship, contains the Privileges or Immunities Clause, the Due Process Clause, the Equal Protection Clause, and deals with post-Civil War issues.
15th February 3, 1870
Prohibits the denial of the right to vote based on race, color
16th February 3, 1913
Permits Congress to levy an income tax
17th April 8, 1913
Establishes the direct election of United States Senators by popular vote
18th January 16, 1919
Prohibited the manufacturing or sale of alcohol within the United States.
19th August 18, 1920
Prohibits the denial of the right to vote based on sex.
20th January 23, 1933
Changes the date on which the terms of the President, VP, Members of Congress end and begin
21st December 5, 1933
Repeals the 18th Amendment
22nd February 27, 1951
Limits the number of times that a person can be elected president
23rd March 29, 1961
Grants the District of Columbia electors in the Electoral College.
24th January 23, 1964
Prohibits the revocation of voting rights due to the non-payment of a poll tax.
25th February 10, 1967
Addresses succession to the Presidency and establishes procedures both for filling a vacancy in the office of the Vice President, as well as responding to Presidential disabilities.
26th July 1, 1971
Prohibits the denial of the right of US citizens, eighteen years of age or older, to vote on account of age.
27th May 7, 1992
Delays laws affecting Congressional salary from taking effect until after the next election of representatives.