This story first appeared on the BBC News website.
The gas tax, a levy on petrol and diesel fuel, was introduced in 1986 and was a key part of the US economy until the 1990s.
It was a major tax, making a lot of cars and trucks expensive and expensively polluting, but it was repealed in 1993 and replaced with a tax on gasoline.
The tax was intended to pay for a large array of social programmes, from healthcare to the infrastructure and education systems of a country, and to pay a lot for the government to subsidise them.
But the tax did not raise much money.
It brought in about $30bn (£21bn) in 1992, but the tax revenue was very low, and it wasn’t really designed to help pay for anything.
So, over time, the government began cutting back the amount of fuel that was being taxed and started to reduce the amount that was taxed.
But there was a big gap in revenue.
In 2002, Congress passed a new tax on petrol, which it called the gas-tax exemption, and so there was no longer any way for Americans to save money.
The gas tax was also not designed to cover the cost of roads and highways, so there were a lot fewer roads built and a lot less money spent on roads and other infrastructure.
That left the country with a lot more debt than it could pay off in taxes.
The US economy went into a tailspin.
In 2009, the US House of Representatives passed a bill, the American Taxpayer Relief Act, which, among other things, included a gas tax relief of $1,000 a year for households making less than $250,000 (£186,000).
This is known as the Buffett Rule, named after Republican Senator and former President Ronald Reagan.
It means that the US government has to pay out a certain amount of tax on the average income of people who make more than $1 million a year.
The Buffett Rule also applies to high-income households making more than the average US household income of $450,000.
But the bill has failed to pass the Senate, which has so far not passed a tax reform bill.
The President of the Senate has not yet indicated that he will sign it.
If the tax cuts on petrol were to expire in 2021, then the Buffett rule would have to be repealed as well.
The current tax code is structured so that people can only benefit from the tax relief on petrol if they make more money than they paid in taxes last year.
So if the tax breaks on petrol are to expire, that would mean that there would be an end to any tax relief that people could have enjoyed from petrol.
And there is no guarantee that it would be possible to save that much money in taxes from 2019.
So there is some risk that people would end up paying more taxes than they otherwise would have.
And so, the current tax system would have been designed to put a brake on tax increases and therefore, as a result, there is a real possibility that the tax bill could not be passed.
In 2019, the House of Representative voted to extend the Buffett Rules for another year, and the Senate will now have to vote on it.
That is the next hurdle that has to be overcome.
The Senate has the votes to pass a bill that is essentially a continuation of the current law, but if the House passes the bill, then President Donald Trump will be able to sign it without any debate, without any votes being needed from the Senate.
If the Senate does not vote on the bill by the end of the year, then Trump will need to sign the bill into law.
There are a lot in between the Senate and the House, and there are several different ways that the president can sign it into law without having to go to a vote in the Senate or the House.
There is the option of signing the bill without a vote from either the House or the Senate as it stands.
That would mean Trump could sign the legislation into law as soon as the President signs the bill.
He could also sign the law into law if he wants to wait until after the Senate votes on the legislation.
This would give the Senate a chance to override any vetoes by the President.
That, however, is not likely to happen because of the filibuster rules.
If, however a vote were to be taken, the Senate would have a two-thirds majority, so if a filibuster were to happen, it would likely be a vote to override a veto.
So that would make it extremely unlikely that the Senate could override a President’s veto.
And the President would have less flexibility than he would have otherwise in how he would sign the bills into law because of that.
However, if the Senate passes the legislation and the President does not veto it, then that would still leave the House and the president with a two weeks’ time window to sign a new bill that contains the changes that have been made.
So the President could sign a bill and then wait