TODAY BOTH HOUSES OF CONGRESS approved a $1.1 trillion spending bill intended to keep government services funded through September 2016. Tucked into this omnibus legislation are provisions that could undermine, on the basis of personal heritage, the ability of many American citizens to travel visa-free to countries in Europe and east Asia.

For more than 25 years, the Visa Waiver Program has allowed people from a select list of countries, currently 38 nations long, to travel to the U.S. without a visa. Those countries, in turn, must reciprocate, allowing Americans the same privilege on their own soil. Today, Congress voted to change the deal: People coming from countries covered under the Visa Waiver Program, including people who are citizens of those countries, will now need to get a visa if they are determined to be nationals of Iran, Iraq, Sudan, and Syria, or if they have visited those countries since 2011.

This is worse than it sounds, because at least two of those countries, Iran and Syria, deem people to be nationals, regardless of where they were born or live, if their fathers are citizens. So it’s possible that someone who is a citizen of one of the countries on the visa-free travel list — the United Kingdom, say — and who lives there and grew up there and has never visited another country, could end up denied entry to the U.S. because of a parent born in Iran or Syria.

It gets even worse still, because there is a strong likelihood that countries party to the newly altered Visa Waiver Program, including European Union member states, will institute reciprocal restrictions on Americans, meaning that many Iranian-Americans, Syrian-Americans, and others in the U.S. would see their ability to travel the world seriously degraded based on ancestry or dual citizenship. Potentially facing similar reciprocal restrictions are any aid workers, journalists, or other Americans who simply visited at some point since 2011 the countries targeted in the new legislation.

An open letter published by the European Union’s ambassador to the United States has already said that passage of the bill “could trigger legally mandated reciprocal measures” against American citizens, in this case, specifically those whose national origin is from Iran, Sudan, Syria, or Iraq, effectively placing them into a lower category of citizenship when attempting to travel abroad.

The new restrictions have alarmed civil rights groups in the United States, including the American Civil Liberties Union, which in a letter to the House of Representatives earlier this month called the changes arbitrary, discriminatory, and “un-American,” since they would punish individuals solely based on their nationality or ethnic origin. Despite this harsh criticism, at least some of the provisions were approved by the House of Representatives in a 407-19 vote on December 8, paving the way for today’s vote.

Jamal Abdi, a spokesperson for the National Iranian American Council, believes the legislation will eventually prompt other countries to deny Iranian-Americans the same rights of free travel enjoyed by other Americans.

“Targeting people who are dual nationals is particularly discriminatory and unjust, since dual nationality is not something you choose,” Abdi said. “Under this legislation, if you’re a European of Iranian origin or your father is an Iranian citizen, you wouldn’t be able to travel without a visa to the United States. As we’ve already heard from the EU, this would trigger reciprocal measures that would result in the passports of Iranian-Americans being treated as inferior, essentially putting them in a category of second-class citizenship.”

The bill approved by the House earlier this month, HR-158, which is related to the legislation approved today, was initially written for the narrow and reasonable purpose of blocking or restricting from U.S. entry individuals who traveled to Islamic State-controlled territory in Syria or Iraq. But provisions later added by Republican lawmakers made the legislation more draconian, including by imposing restrictions involving entire countries — official “state sponsors of terrorism” like Iran and Sudan. (In those two countries, at least, the Islamic State is nonexistent.)

Some parts of the newly passed legislation could even violate the recently negotiated deal between the U.S. and Iran to curb Iranian nuclear activity.

For example, under the new rules, a European or Japanese business owner who traveled to Iran to take advantage of recently lifted economic sanctions would thereafter find themselves denied visa-free entry to the United States — a restriction that would inevitably act as a deterrent to doing business in Iran. But the provisions of the U.S.-Iran nuclear deal prohibit policies that undermine “the normalization of trade and economic relations with Iran.”

Thirty-three Democratic members of Congress signed an open letter published last week criticizing some of the new Visa Waiver Program restrictions. The letter said the restrictions “would result in discrimination against people simply because they are dual citizens based on ancestry” and asserted that national origin should not be a factor when determining visa requirements. People entering the United States, the letter said, should be evaluated on an individual level, not based on “where their parents are from.”

In the end, those objections were not enough to stop the new rules. Abdi said that politicians have stoked fears of immigration and helped increase public support for harsh laws that target en masse individuals from Muslim-majority countries.

“This bill is a direct response to the rhetoric of GOP leaders like Donald Trump and others who have called for restricting people coming to the United States based on national origin,” Abdi said. “There has been a lot of outcry about his outrageous comments and proposals from the public and in the media, but now as a consequence of the environment he’s helped create, we’re actually seeing Congress take steps to turn such xenophobic ideas into law.”