If you casually pay attention to US news, you probably think life is getting much better for gay Americans. Unfortunately, not in my home state of Indiana. On Monday, the Indiana state senate voted in favor of a constitutional amendment that would define marriage as between a man and a woman only.

It's not a done deal. State lawmakers will have to approve the amendment again and then all Indiana voters will get their chance to weigh in. But Monday's vote sends a very negative message to LGBTQ people in Indiana – and those who support their rights. And in case anyone needs a reminder, Indiana is not the only state with some type of ban in place or in process.

Here's what conservative lawmakers should understand before voting to enshrine intolerance in a state constitution: young people and businesses are likely to leave states that don't support marriage equality.

The private sector overwhelmingly opposes Indiana's proposed ban, known formally as HJR-3. One of Indiana's largest companies is Eli Lilly. Its Senior VP of Human Resources, Stephen Fry, stood before a legislative committee to make the case that top talent would go to competitors in other states for employment. Marya Rose, Chief Administrative Officer at Cummins Inc, claimed HJR-3 would cause "irreparable harm" to the business climate in Indiana, and threatened to slow job growth within Indiana operations.

The data back up these concerns. Recently, Rebecca Townsend of Nuvo sat down with researcher Jeramy Townsley who ran statistical regression models with startling findings. Townsend reports that:

New regression analysis from a local sociology prof suggests that the economic performance of Great Lakes states with statutes or constitutional amendments banning same-sex marriage lags behind those without restrictions.

How do we tell businesses – small and large – and startups that we can justify threats to their business because Indiana wants to be unwelcoming to certain Americans?

Indiana's Republican state legislators face an interesting choice: do they side with a largely evangelical Christian perspective or the private sector perspective? Will they listen to Pastor Dan or will they listen to CEO Dan?

Frankly, I think they should listen both. As a young gay conservative, I'm exactly the kind of person Indiana lawmakers should want to attract and keep in the state. I believe that family values and pro-business values are good for our society. I believe that marriage is good for gay people too, just like I believe it was good for my grandmother and grandfather when they helped build the legacy of my family.

On the verge of graduating from college, one of the largest decisions of my life boldly awaits: do I stay or do I leave Indiana? With or without a constitutional ban on the freedom to marry, a statutory ban still exists in Indiana and in other states. It's a big deterrent. I'd rather look for jobs in a more welcoming state.

Community is important to millennials. We want to establish strong families and live prosperous lives among friends. When states seek to restrict liberties, such as the freedom to marry, millennials – both gay and straight – see those efforts as a threat to strong families and communities. My generation wants to be a part of a state that looks to the future, instead of one that looks backward.

For millennials, the freedom to marry is a component of quality of life. What will ultimately influence young millennials' decisions on whether to stay in or leave Indiana (and other states with similar laws) is whether or not they can visit their neighbors with a good conscious. For many people in my generation, even conservatives, the atmosphere to make meaningful change – inside and outside the workplace – ranks higher than the state's low tax rate.

I can be a young conservative anywhere. But when it comes to being a young gay conservative who hopes to marry and have a family one day, I am forced to think longer and harder about where I might live.

I've considered high-tax states like California or Washington. I've considered the bureaucracy and regulation in big cities like Chicago or New York. But you know what is increasingly hard to consider? A state that claims to be business "friendly and prosperous", but at the same time has gone so far as amending the constitution to prevent thousands of its own citizens from having the opportunity to marry.

In Indiana, the HJR-3 debate has been the last straw for many innovative young millennials whose talents can easily be taken elsewhere.

The anti-gay marriage ban does not represent the conservative, small business community values my grandpa instilled in me – a man who lived the American dream, who built a small Italian restaurant on the east side of Indianapolis. And you know what? The ban also doesn't represent the strong, conservative family values that were instilled in me by my other grandpa, a man who worked tirelessly as a mechanic for American Airlines for decades.

Oscar Wentzel didn't care who you were. He cared that you built a strong family and passed along a legacy in a community that you cared about. Today, he wouldn't appreciate that his grandson couldn't solidify that process through a marriage in the state of Indiana.