On a cool, bright day last November, hundreds of journalists, environmentalists, and politicians gathered on the outskirts of Denver to watch U.S. officials drop almost six tons of contraband elephant ivory into a mobile-home-sized rock crusher. The rumbling machine soon reduced the raw tusks and tourist carvings into piles of pebbles and clouds of sour-tasting dust.

The ivory represented most of the U.S. government stockpile, and it had been seized from smugglers, tourists, and illegal sellers over the previous 25 years. Its dramatic destruction was designed to send the message that the U.S. was taking the lead in fighting the scourge of poaching, which now kills an estimated 35,000 of Africa’s elephants annually, about one-tenth the remaining population.

The "ivory crush" capped a year of strong rhetoric from U.S. government and conservation nonprofits that had framed the illegal killing of elephants as a threat to national security – ivory profits, the message has been, fund terror groups. The burgeoning demand for ivory in Asia was blamed for the upsurge in poaching, with China cited as the largest market, followed, most experts said, by Thailand and Vietnam.

Yet amid all the media coverage, little attention has been paid to the U.S.’s own trade in legal and illegal ivory, which experts say, trails only the very largest Asian markets. It’s legal to sell African elephant ivory imported before 1989 and Asian elephant ivory removed from the wild before 1976 within the U.S., and illegal sales regularly occur under cover of the legal market – a ton of illegal ivory was seized in a single raid on New York stores in 2011. Ivory in the U.S. is largely unmonitored, and the laws regulating it are antiquated, confusing, and shot through with loopholes. In addition, the agencies tasked with enforcing these laws are underfunded and chronically short-staffed.

If 2013 was a year of talking about ivory trafficking, conservationists hope that 2014 will be a year of action. This week, the Obama administration announced that it will change regulations in the coming months to ban interstate sales of all ivory except certified antiques; limit elephant trophy imports to two per hunter; cut off commercial imports of antique ivory; and increase certification requirements for the remaining trade.

While conservation groups are applauding these planned moves, they note that Congress needs to pass additional laws to increase penalties for violations and approve additional funding needed for enforcement. The U.S., conservationists say, still has a lot of work to do.

Edward Grace, deputy assistant director for law enforcement at the U.S. Fish & Wildlife Service, calls the U.S. "a large consumer of ivory." Although recent ivory seizures in Asia dwarf those made in the U.S., he says, "you can go into New York City, you can go into Washington D.C., you can go into San Francisco, and there’s ivory for sale.

"The price of [raw, uncarved] ivory ten years ago was less than $1,000 a pound," but it now sells for "almost $1,500 a pound," says Grace, which indicates steady or increasing demand.

In 1989 the U.S. enacted the African Elephant Conservation Act, which placed a moratorium on the import of most African elephant ivory. Under the terms of the act, ivory imported into the U.S. before 1989 – called ‘pre-ban’ ivory – is legal to own, use and sell. Ivory imported after the law went into effect is generally not legally saleable, unless it’s a worked antique item that is at least a hundred years old, in which case its sale is allowed under a so-called "antiques exemption."

According to figures recently sourced from government agencies by the International Fund for Animal Welfare (IFAW), more than 7,500 ivory carvings and 1,746 elephant trophies (with two tusks apiece) were legally imported into the U.S. between 2009 and 2012. Thousands more ivory pieces, and hundreds, perhaps thousands, of loose tusks were legally imported during the same period. IFAW found that ivory valued at more than $1 million was available for sale via online auctions in a single month in 2013.

The fact that pre-ban and antique ivory is legally sold, generally without certification, presents a serious problem for law enforcement. Even with high-tech tools, there’s often no way to tell pre-ban from post-ban ivory, or a real antique from a new piece of ivory that’s been distressed or discolored to look like an antique. Authorities can find it impossible to tell African elephant ivory from Asian elephant ivory, which is regulated under different laws, or from any number of other ivory-like substances: mammoth ivory, hippo teeth, walrus teeth, warthog tusks, and so on. Many times the only means of identifying specific types of ivory is via expensive, destructive lab tests, says Grace.

As a law enforcement agent going into a store, he says, "if you ask how old the ivory is, the first thing you’re going to get is it’s either a hundred years old or it’s pre-ban – and a lot of times that’s based on nothing.

"It’s not like you walk into a store and find someone selling cocaine, which is illegal on its face."

Pending implementation of measures proposed by the Obama administration this week, there currently is no requirement for an item of pre-ban ivory to be officially certified or documented, and its sale does not need to be recorded. Antique ivory must be certified under the Convention on International Trade in Endangered Species (CITES) if it’s to be imported or exported from the U.S,. but its mere possession does not require that.

In addition, a 1997 U.S. Court of Appeals ruling weakened the 1989 African Elephant Conservation Act by shifting the burden of proof on to the government in ivory cases: To successfully prosecute someone under that law, the government now has to show that he or she knew they were in possession of or selling African elephant ivory imported after 1989 and also knew this was illegal.

"The illegal ivory is hidden a lot of times in plain sight, with dealers claiming it’s legal ivory," says Grace. He notes that cases against sellers of illegal ivory usually have had to be built through expensive, time-consuming undercover investigations. "We’ve got to work into these groups so [they] will tell us. ‘Oh, we know this ivory’s not a hundred years old’."

The proposed regulatory changes will place the onus on ivory sellers to provide documents to prove an object’s origins and age, which, say agents, should significantly ease enforcement.

The Fish and Wildlife Service has about 200 agents across the U.S., and a single ivory or rhino horn investigation can occupy up to 30 agents and take 18 months. Grace notes the overstretched agency has the same number of agents as it did in the late 1970s, even though "many more species have been added to the Endangered Species Act," which the service is charged with enforcing. Federal officials have not clarified how they plan to increase staff levels in light of the newly announced enforcement strategy.

A handful of states including New York, Illinois, and California have passed state ivory laws, and others, like Hawaii, may do so soon. These can assist law enforcement — New York, for example, requires ivory dealers to have a permit, which discourages some illegal traders. But the patchwork of state and federal laws tends to confuse consumers and can further complicate enforcement.

The simplest situation in which to prosecute ivory traffickers has been when they bring illegal ivory across U.S. borders, according to Grace. Transporting illegally taken (poached) or illegally sold ivory across national or state borders is a violation of wildlife and smuggling laws, which carry heavy penalties. But many ports of entry don’t have trained wildlife inspectors, and much cargo — for example, ship-borne containers — is not inspected at all.

Although ivory sale restrictions enacted by relatively simple regulatory changes and state legislatures could be an important tool to slow the illegal trade, there are important legislative actions that only Congress can take, says Ginette Hemley of the World Wildlife Fund-US, particularly with respect to increasing the penalties for ivory trafficking.

"We want to see wildlife crimes treated as serious crimes," she says, "which means invoking other statutes for example which apply to narcotics trafficking and money laundering and serious fraud.

"We want to see a broader suite of actions that really puts teeth into the system."

Many conservationists are concerned that any restrictions on ivory sales and imports might be weakened in the future in the face of opposition from antique auction houses that sell high-value goods containing ivory and from sport hunting organizations.

Washington-based sources who did not want to be named told me that restrictions on the importation of sport-hunted elephant trophies and tusks were unpopular among members of Congress, some of whom are enthusiastic sport hunters themselves. "No one [in Congress] will talk to us about ivory if we mention restrictions on sport-hunted trophies," says one policy advocate for a large nonprofit organization.

The Fish and Wildlife Service’s official position is that controlled hunting does not represent a threat to African elephant populations, although it does acknowledge that some sport-hunted ivory has been illegally sold on the black market. And the figures obtained by IFAW indicate that more elephants are legally killed by U.S. hunters than are poached in some African countries.

Beth Allgood, IFAW’s campaigns manager, emphasized that new regulations and laws regarding ivory need to be as simple and easy to enforce as possible. "Whatever gets done through whatever process, it just can’t be complicated," she says.

The U.S. "has a major problem at home" says Elizabeth Bennett, vice president for species conservation at the Wildlife Conservation Society, "but historically, the U.S has led the way in terms of species conservation for the whole world through its Endangered Species Act and its contributions to CITES.

"From that point of view alone, even if it’s not the single biggest market [for ivory], it could really set an example by addressing it."