President Donald Trump has signaled that he would be open to raising the gas tax.

Trump told Bloomberg that he "would certainly consider" increasing the gas tax "if we earmarked money toward the highways."

Here are five things to know about Trump considering to raise the gas tax.

1. The gas tax is not mentioned in his tax reform proposal. This means that the specifics of a higher gas tax under Trump are currently unknown. It also unclear if Trump would insist that a tax reform bill that reaches his desk include a higher gas tax. But the fact that Trump has indicated that he might be willing to sign it into law is certainly disconcerting.

2. Increasing the gas tax would particularly harm the poor. The person who inadvertently made this case was, ironically, Barack Obama.

In 2011, Obama stated, "For Americans that are already struggling to get by, a hike in gas prices really makes their lives that much harder. It hurts."

Obama wasn't specifically talking about a higher gas tax there, but The Daily Caller noted that the same logic applies to a higher gas tax that Obama was proposing in 2016 since basic economics indicates that a higher gas tax would result in higher gas prices.

Additionally, according to The Heritage Foundation, consumers wouldn't drive less as a result of a higher gas tax; they would instead "make other sacrifices" and that "on average, an increased gas tax would cost families who drive $54 per year." Naturally, this adversely hurts the poor, who have less financial leeway.

3. A higher gas tax wouldn't help to repair the country's infrastructure. The Daily Wire has previously explained:

Proponents of the infrastructure spending would likely counter that Trump would be rebuilding the country's infrastructure, not start new projects. But economist Thomas Sowell noted in a 2009 column that repairing infrastructure isn't what scores political points, it's the "ribbon-cutting ceremonies that give politicians favorable free publicity in the media. But nobody holds ribbon-cutting ceremonies for filling in potholes or repairing bridges." There's no question that Congress would ensure that those ribbon-cutting ceremonies continue; Trump's ego is enough for him to want to have some of those ribbon-cutting ceremonies for himself. There is every reason to believe that infrastructure boondoggles would continue, therefore creating serious time lags.

Therefore, it's unlikely that the higher gas tax would result in repairing the highways, which was Trump's rationale for being open to it.

4. There is no dire need to fix the country's highways. The Heritage Foundation cited a Federal Highway Administration report that found "that the percentage of vehicle miles traveled on the national highway system with 'good' ride quality increased from 48 percent in 2000 to 60 percent in 2010, while the share with 'acceptable' ride quality grew from 91 percent to 93 percent." This is in line with the Cato Institute stating in 2014, "the average smoothness of our roads has increased every year."

That means the entire premise for Trump's openness to a higher gas tax is flawed.

5. The last time the gas tax was increased was 1993. Richard LeFrak, CEO of the real estate firm LeFrak, who is advising Trump on his infrastructure proposal, told Fox Business' Maria Bartiromo in March that the gas tax has become "a little bit the third rail of politics for Congress," which does certainly raise questions as to whether Congress would be willing to let such a tax increase pass, but anything is possible given the Republicans' penchant for surrender.

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