PHOENIX – National security has been one of President Donald Trump’s key agenda items since he became a candidate for the office.

But where is that wall?

If it gets built, it is not going to be quickly, but the ball is rolling.

Back in July, the House passed a $788 billion spending bill. $1.6 billion of that would serve as a down payment to start construction on new sections of the wall along the U.S.-Mexico border.

The president promised to fix all of the U.S.'s immigration-related issues, including gangs like MS-13 and the drugs that cross our border.

White House officials say arrests along the border have dropped by 46 percent this year so far, compared to last year. Deportations have increased by 32 percent.

That progress is without the planned wall.

So, is it simply a campaign promise Mr. Trump wants to keep, or is it a necessary border security measure?

The president said his visit to Yuma Sector Border Patrol, before landing in Phoenix, only reinforced his goal.

“I said [to Border Patrol agents] 'How important is the wall to some of the folks?'” the commander is chief recalled during his re-election campaign rally in downtown Phoenix Tuesday night. “… And they looked at me and said, 'It's vital. It's vital.'"

So vital, perhaps, that he may even allow a government shutdown.

"The obstructionist Democrats would like us not to it, but, believe me, if we have to close down our government, we'll build that wall,” said Trump.