As Republicans in the Congress finally roll out the details this week of their tax reform bill, that measure has morphed into the best chance - maybe the only chance - for a major GOP legislative victory on Capitol Hill in 2017, as President Donald Trump continues to argue that GOP lawmakers will overcome any internal party divides, and get the job done on the first major tax reform package since 1986.

"Do not underestimate the UNITY within the Republican Party!" the President tweeted on Friday.

"This will be the biggest TAX CUT in the history of our country - and we need it!" the President said late last week, though he has spent more time in recent days talking about issues related to Russia, Hillary Clinton and the 2016 campaign.

Here's where President Trump's agenda stands on Capitol Hill.

1. After the health care debacle, the pressure is on over tax reform. In recent weeks, a number of GOP lawmakers have made clear in the hallways on the Capitol that they need to pass a tax reform bill - no matter what. "We've got to get something major done," said Rep. Mark Meadows (R-NC), the head of the House Freedom Caucus, as he admitted to reporters that he would be more likely to accept a deal, even if he doesn't like some of the tax reform fine print. Back in January, it was just a question of 'when' health care reform would pass, and how swiftly the GOP would get to tax reform. It didn't turn out that way, and now, President Trump needs a legislative victory on tax reform - in a bad way.

2. A compressed time frame on tax reform for the GOP. Back in 1986, it took 13 months from the time the original draft of a tax bill was released in the House to get to a bill signing at the White House. In 2017, the GOP wants to go from releasing a tax bill on November 1 to having the President sign something by Christmas. That's a seven week period - with the Thanksgiving break in between. Tax reform is extraordinarily complicated, and this bill will be filled with all sorts of important changes that remain secret at this point. There will be a huge reaction from all sorts of lawmakers, industries, and lobbying groups once the details come out on Wednesday. I would say the more that the GOP bill turns into a 'tax cut,' the better chance of swift action. The more that the bill is actual 'tax reform,' the bigger the chance that it could take longer to get through the Congress - or get derailed, like a GOP plan to overhaul the Obama health law. This weekend, one major group - the National Association of Home Builders - came out against the Republican effort. I will say this again - this is complicated, and it won't be easy for the GOP.

3. There is still no Trump infrastructure proposal. For over a year, President Trump has talked about his plans to spur new construction of roads and bridges in the United States, repeatedly trumpeting his $1 trillion plan that would create new jobs and help for the economy. But despite all sorts of White House meetings and statements by Mr. Trump, there is no plan. There is no bill.  In Congress, Republicans have issued no plan. The original idea from the President was a 'public-private partnership' that would use seed money from Uncle Sam to spur private construction of new infrastructure. But now, President Trump says he doesn't support that - and reiterated exactly that in a recent meeting with Senators. There had been some speculation that an infrastructure plan might be included in the tax bill - we'll see. There was even talk last week of a higher gasoline tax to pay for new roads and bridges, an idea that is hotly opposed by most Republicans.  The last time the federal gas tax was raised?  1993.

4. Trump keeps adding to his agenda in Congress. Even though Congress was unable to act on health care, and there is no guarantee that lawmakers will be able to approve a measure on tax reform, the President in recent weeks has been adding even more hot-button items to the Congressional agenda, asking lawmakers to approve major plans to crack down on illegal immigration, and calling on the Congress to approve new laws to limit the growth of Iran's nuclear ambitions. At this point, it's not even clear that Congress will do anything related to immigration and the DACA, both of which may be as paralyzing an issue in the House and Senate as health care. Earlier this month, the President threw another item into the mix, saying he wants lawmakers to reform rules on welfare. The White House has given no hints on what it wants done, or why that subject was mentioned out of the blue by Mr. Trump in a recent Cabinet meeting. Add it to the Capitol Hill to-do list - that isn't getting done in 2017.

5. Still to be dealt with - a year-end spending deal. With the federal government operating on a temporary spending plan that runs out on December 8, there are really no signs yet of deal making on a year-end spending agreement between Democrats and Republicans - and the White House.  A number of major issues have been tossed around as possible add-ons to that plan, like legislation to deal with illegal immigrant "Dreamers" and immigration, money for Mr. Trump's border wall, and more. Think about it this way - that bill could be a big Christmas Tree for all sorts of legislative extras that both parties want - if you could get agreement on a big December deal.  As for spending on the federal government, GOP lawmakers are quietly saying that they expect that plan will increase spending for both the Pentagon and domestic programs - since it will need Democratic support, an outcome that won't please fiscal hawks in the Republican Party. The uncertainty has left a lot of issues on hold, as we wait to see how they are handled later this year.