Well, as tempting as it is to try and make interpretations and predictions for the future as well as speculate what kinds of events would decelerate or accelerate these trends, I think it is more powerful if I leave all that to your own imagination!
If you want to do something about altering this trend, one way or another, visit the links below. The case is quite solid that the vast majority of overall population growth in the USA since the 1970 census is due to immigration.
If you are not bothered about this trend or think it is a good thing, then take no action and for your part you will have helped make it happen in your own way.
Immigration Reduction Organizations:
Numbers USA
FAIR
Project USA
American Patrol
The Minuteman Project
Center for Immigration Studies
Americans for Immigration Control
Immigration Reform Caucus
immigrationwatchdog.com
Those Opposed to Immigration Reduction:
(and/or actively promoting more immigration, legal and/or illegal)
National Council of La Raza (translates to 'The Race')
Ford Foundation
National Restaurant Association
U.S. Chamber of Commerce
Conference of Catholic Bishops
The Democratic Party
The Republican Party
American Green Party
American Communist Party
American Socialist Party
President George W Bush
John F Kerry, Democrat 2004 Presidential candidate
Hillary R Clinton, leading Democrat 2008 Presidential candidate
John McCain, leading Republican 2008 Presidential candidate
AFL-CIO
Moveon.org
The Essential Worker Immigration Coalition (EWIC)
Southern Poverty Law Center
Anti-Defamation League
ACLU
National Center for Lesbian Rights
Immigration Equality
People for the American Way
American Immigration Lawyers Association
American Jewish Committee
Mexican American Legal Defense Fund
Department of Homeland Security
La Voz de Aztlan
MEChA
Oops, forgot to link to these groups! Will have to add that to my To-Do list...