Kevin Sabet, a former drug adviser to three U.S. administrations, including President Obama, said marijuana remains illegal on the federal level and the measures in Colorado and Washington "will be curtailed."
Governors in Colorado and Washington said they planned to talk by phone with U.S. Attorney General Eric Holder about the measures, according to the Associated Press Nov. 9.
If the laws are implemented in the two states, for the first time in U.S. history adults will be allowed to possess small amounts of marijuana for recreational purposes. A similar initiative was rejected in Oregon Nov. 6.
"When you have the governors of both states as well as the president and Congress already determined that marijuana is illegal, this is not going to be a walk in the park for marijuana enthusiasts," Sabet told ABCNews.com.
The Justice Department said enforcement of the federal Controlled Substances Act "remains unchanged," according to Reuters.
"We are reviewing the ballot initiatives and have no additional comment at this time," a government statement said.
Sabet said the federal government won't "take this lying down," and he expects the issue to be tied up in courts for a long time.
"The government has multiple avenues. They can wait until it's implemented, take action before it's implemented, reiterate what federal law is, send warning letters," Sabet said.
Perhaps an unintended consequence of voters' actions in Colorado and Washington is the effect that marijuana legalization in the United States will have on the drug war in Mexico.
A top aide to Mexico's President-elect Enrique Pena Nito said the new laws will complicate his country's commitment to stopping the growing and smuggling of marijuana, according to The Washington Post.
"Obviously we can't handle a product that is illegal in Mexico, trying to stop its transfer to the United States, when in the United States, at least in part of the United States, it now has a different status," Luis Vidagaray said Nov. 7.
Mexico's new president is scheduled to meet with Obama in Washington in three weeks, and the aide said marijuana laws are sure to be a priority in talks between the two leaders.
"The legalization of marijuana forces us to think very hard about our strategy to combat criminal organizations, mainly because the largest consumer in the world has liberalized its laws," Manlio Fabio Beltrones, leader of Pena Nito's party in Mexico's Congress, said, according to The Post.
FoxNews.com predicted that Mexico's president-elect would pressure the Obama administration to strictly enforce U.S. federal law. The current Mexican administration, headed by Felipe Calderon, "vehemently opposed" pro-marijuana measures in the United States, FoxNews.com said.
A former Mexican official told AP it's slightly likely that the loss of income to marijuana cartels might lead them to branch into other criminal activities.
Also in the wake of the votes in Colorado and Washington, people were wondering whether the states would become destinations for marijuana tourism. As long as visitors to the states purchase and use the drug while in those states, they would be within the bounds of the new laws, AP said.
Some were comparing the possibilities to Amsterdam, which has marijuana cafes. Experts said it's reasonable to assume entrepreneurs will try to take advantage of the new laws.
In Colorado's top tourism towns, support for legalized marijuana was strong, AP said. Aspen approved the measure 3-to-1, more than two-thirds of Vail backed it and nearly 8 in 10 voters favored the initiative in Telluride.
A Denver tourism official, though, expressed regret over the outcome of the vote.
"Colorado's brand will be damaged, and we may attract fewer conventions and see a decline in leisure travel," Richard Scharf, CEO of Visit Denver, said.
Concern about public health has been another topic of conversation now that two states have liberalized marijuana laws. Unless the federal government prevents implementation, the laws will lead to a public health experiment, experts said.
Legalizing marijuana clearly has the potential to harm people, Rosalie Liccardo Pacula of the Drug Policy Research Center told FoxNews.com.
The drug temporarily impairs memory, coordination and perception, and studies indicate people who drive within a few hours of using marijuana are more than twice as likely to be involved in a car crash compared to other drivers.
Legalized marijuana in Colorado and Washington most likely will lead to an increase in use by teenagers, Pacula said.
A study in Colorado found that among teenagers receiving treatment for substance abuse, nearly 75 percent had used medical marijuana that was recommended for someone else -- something now called "diverted" medical marijuana.
Eighteen states and the District of Columbia have legalized marijuana for medical purposes, including Colorado, Washington and Oregon.
Compiled by Baptist Press assistant editor Erin Roach. Get Baptist Press headlines and breaking news on Twitter (@BaptistPress), Facebook (Facebook.com/BaptistPress ) and in your email ( baptistpress.com/SubscribeBP.asp).
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