Lee H. Hamilton, a U.S. representative from Indiana from 1965 to 1999, is director of the Center on Congress at Indiana University. David C. Williams is executive director of the Center for Constitutional Democracy and a professor of law at Indiana University’s Maurer School of Law.

The recently signed trade and investment framework agreement between the United States and Burma gives the Obama administration tools to push President Thein Sein’s government toward greater reform. The United States should use those levers to promote not only equitable business ventures but also fundamental political reform. The keynote of U.S. policy must still be to support democratization and human rights, not merely closer economic ties.

Some have cautioned that the Obama administration is warming too quickly to a country where reform is still in its infancy. But the framework commits the United States to nothing; it merely provides a platform for discussing cooperative business initiatives. Because the Burmese government deeply desires such projects, the agreement gives the United States an opportunity: In exchange for new economic ventures, the U.S. government should demand that Burma expand and hasten its reform efforts.

The Obama administration’s statements suggest that it will use this leverage primarily to ensure that economic projects benefit the poorest Burmese people and respect the rights of workers, as well as to promote reforms that will lead to a better investment climate, such as transparency and the rule of law. The administration should go further and use its influence to bring about fundamental constitutional change.

Burma’s biggest problem is not a poor investment climate; it is a massive over-concentration of power in the wrong hands. President Obama has repeatedly called for the release of political prisoners and an end to sectarian violence against Burmese Muslims. Yet these concerns are only part of the problem. Two other issues affect even more people: the military’s continuing power and its war against ethnic minorities.

Under Burma’s constitution, the army is not subject to the civilian government; within its broadly defined sphere, it can do whatever it wants. The president is not commander in chief. Nor can the courts take jurisdiction over military abuses. The military has also asserted that it is the ultimate authority in the peacemaking process with the ethnic resistance armies.

Burma’s ethnic minorities went into armed resistance because they felt that the 1947 constitution subjected them to the control of the majority ethnic group, the Burmans. Minority leaders also unanimously believe that the current constitution, adopted in 2008, fails to meet their needs. Many are seeking promises of constitutional change as part of a comprehensive peace accord.

But Burma’s military has consistently obstructed the peace process. The civilian government has entered into cease-fires with most of the resistance armies, and Thein Sein has ordered the army to cease attacks. Nonetheless, in many parts of Burma, the army continues to assault not only the armed opposition but also the civilian population, insisting that it has final authority over matters of war and peace — as, under the 2008 constitution, it does. While the world has appropriately looked closely at sectarian violence in Burma, it has placed in softer focus the spectacle of a sovereign state waging war against its people.

Many ethnic minority leaders insist that constitutional reform must come before large-scale economic development. They believe that under the current constitution, development will benefit only civilian and military leaders and their cronies — no matter how carefully the United States tries to ensure an equitable distribution of proceeds. Already, many ethnic minorities are losing their resource-rich lands to government-sponsored developers; the money is flowing like a pipeline to the new capital of Naypyidaw. Once the United States has invested heavily in the Burmese economy, minority leaders believe, the government will have no incentive to make constitutional changes.

It may be premature to try to reduce the military’s power because there is still a risk of a coup. But it is not too soon — and may soon be too late — to amend the constitution to address the concerns of Burma’s ethnic minorities.

The problem is that the military controls 25 percent of the seats in Burma’s legislature — enough to block any constitutional amendments through the normal procedure. Burma therefore needs an extraordinary mechanism to amend the constitution. In the historic 1947 Panglong Conference of ethnic leaders, Gen. Aung San promised the country’s minorities an equitable share of power. Sadly, he was assassinated before he could try to make good on his promises.

It is time to make good on the old promises. The trade and investment framework agreement gives the U.S. government an opportunity to help. Obama should meet with Burma’s minority leaders, just as he recently met with Thein Sein. And he should make clear that economic development must go hand in hand with constitutional change to ensure the safety of not only American investments but also the Burmese people.