(CNN) President Donald Trump makes a hard turn Wednesday from offering empathy to grief-stricken Pittsburgh to the fear and fury of a midterm election closing argument designed to drive up Republican turnout despite the risk of deepening national divides.

The President will launch an eight-state, 11-rally race to Election Day next Tuesday brandishing hardline rhetoric on immigration as he tries to wrest back control of a campaign that was muted by a week of tragedy and national anxiety.

Trump had already complained that controversy over mail bombs allegedly sent by one of his supporters to his top targets in politics and the media was being drummed up by his critics to quiet GOP momentum.

Then the mass shooting at a Pittsburgh synagogue on Saturday, in which 11 people died, sparked a debate over the extent to which Trump's rhetoric was responsible for offering validation to white nationalists and extremists.

The President and the first lady traveled to Pittsburgh on Tuesday to visit the Tree of Life temple, where the shooting rampage took place, and comforted several police officers wounded in the attack.

The President was keeping a promise that he would visit to show support. His spokeswoman Sarah Sanders said Trump found his time in Pittsburgh very moving and "very humbling and very sad."

Some local and civic leaders had asked him not to come while the funerals took place, and his arrival sparked some protests.

On Wednesday, Trump tweeted his grievance over that visit: "Melania and I were treated very nicely yesterday in Pittsburgh. The Office of the President was shown great respect on a very sad & solemn day. We were treated so warmly. Small protest was not seen by us, staged far away. The Fake News stories were just the opposite-Disgraceful!"

Melania and I were treated very nicely yesterday in Pittsburgh. The Office of the President was shown great respect on a very sad & solemn day. We were treated so warmly. Small protest was not seen by us, staged far away. The Fake News stories were just the opposite-Disgraceful! pic.twitter.com/9B9HgCF1G9 — Donald J. Trump (@realDonaldTrump) October 31, 2018

A White House official said there had been discussion of scheduling the visit later in the week but the optics of sandwiching it into a campaign swing were problematic.

The President is making clear he will not tame the incendiary political mood that his critics warn is fostering violence. Quite the opposite. He is signaling an intense and negative end to the campaign.

He is renewing charges that journalists are "enemies of the people" and seeking to whip up fervor among conservatives with an onslaught on immigration, the issue that first animated his political career and to which he returns each time he needs a comfort zone.

In an interview with Axios, Trump dramatically proposed ending birthright citizenship by executive order, even though doing so would be nearly impossible because it would involve the cumbersome process of amending the Constitution.

Trump is also sending 5,200 troops to the US-Mexico border, to prevent what he has styled as an invasion by a group of desperate migrants who are trekking slowly toward the United States.

"Our military is being mobilized at the Southern Border. Many more troops coming. We will NOT let these Caravans, which are also made up of some very bad thugs and gang members, into the U.S. Our Border is sacred, must come in legally. TURN AROUND!" he tweeted Wednesday.

Our military is being mobilized at the Southern Border. Many more troops coming. We will NOT let these Caravans, which are also made up of some very bad thugs and gang members, into the U.S. Our Border is sacred, must come in legally. TURN AROUND! — Donald J. Trump (@realDonaldTrump) October 31, 2018

Trump well knows he can't simply change the Constitution with a stroke of a pen. And he understands that the migrants are 1,000 miles from the US frontier and pose no realistic threat to Americans, for months at least.

But by staking out radical positions on immigration and invoking a sense of a nation under siege, he incites a volatile debate that serves to enliven Republican base voters who he needs to turn out in numbers approaching his shock White House win next Tuesday.

And he shows yet again that he is willing to push his constitutional powers and the instruments of his government -- the military, for example -- in politicized efforts to retain and maximize his power.

Fear plus prosperity is closing presidential argument

Trump's counselor Kellyanne Conway denied the President was adopting a scorched earth strategy to whip up enthusiasm among grass-roots conservatives, contradicting legal experts, including her husband, who believe birthright citizenship is guaranteed by the 14th Amendment.

"if only the base had voted for him he wouldn't be President," Conway told reporters.

"I understand that that's the Sesame Grover word of the day -- that, fear and some other stuff -- but no, it's not whipping up the base."

In a more conventional campaign, the President would do more than Trump has to tout the motoring US economy and low jobless numbers, factors that Republicans hope will mitigate the losses that are historically suggested when a President's approval ratings are below 50%.

But while the President often gets distracted from his talking points, his 2020 campaign team is getting to work.

In a new ad t hat acknowledges the open secret that Trump is interested in the election that's two years off as much as or more than the one next Tuesday, the President's campaign argues that economic prosperity will founder if Democrats win back power in Washington.

"Sometimes success can bring complacency. We have to go remind them. We have to remind them that the economy is not just a given in the United States. It actually takes work," Trump campaign manager Brad Parscale told CNN's Dana Bash.

Trump will begin his final midterm election swing on Wednesday night in Florida, the epicenter of two acrimonious and tight races -- for a Democratic-held Senate seat and the Republican-run governor's mansion.

The effort by Repubican Gov. Rick Scott to unseat Democratic Sen. Bill Nelson and the unexpectedly strong bid by Democratic Tallahassee Mayor Andrew Gillum to beat GOP former Rep. Ron DeSantis in the gubernatorial race are playing out as part of a national referendum on Trump's presidency and are steeped in some of the toxic forces percolating in national politics.

Over the weekend, for instance, the President unleashed a fearsome attack on Gillum, who is African-American, branding him a "thief" in what many observers saw as a racially tinged attack.

In Florida there is a choice between a Harvard/Yale educated man named @RonDeSantisFL who has been a great Congressman and will be a great Governor - and a Dem who is a thief and who is Mayor of poorly run Tallahassee, said to be one of the most corrupt cities in the Country! — Donald J. Trump (@realDonaldTrump) October 29, 2018

Trump sticks mostly to friendly territory

The President will make further stops in Missouri, West Virginia, Indiana, Montana, Florida, Georgia, Tennessee and Ohio in the coming days, often reeling off a double header of rallies.

His itinerary offers a clue to how the election may turn out. Most of his stops are in support of Republicans who are trying to capture or retain Senate seats in states where he won big during the 2016 election.

Though his rallies will swamp multiple media markets, there is not much sign that Trump can be a lot of help to severely threatened Republican incumbents in suburban districts where his brazen manner could be a liability.

The President did, however, spend time in the last few days tweeting out endorsements of Republicans in wobbling House districts.

It remains unclear how the last week of violence and political recriminations will affect the election in its crucial final days.

But with early voting underway in many states, conventional wisdom is solidifying that Republicans will keep control of the Senate but that Democrats have an increasingly good chance of seizing back the House of Representatives.

In that scenario, Trump's final road trips will at least offer him a chance to claim that he won the Senate election -- even as he girds for two years of misery and investigations should Democrats win back control of House committees.

One prominent Republican, Rep. Ryan Costello of Pennsylvania, who is leaving the House, warned on Tuesday that Trump's birthright gambit was a major mistake.

"We all know challenges of suburban R's. The bloc of competitive R held districts less impacted by POTUS thus far are those w high # of immigrants. So now POTUS, out of nowhere, brings birthright citizenship up. Besides being basic tenet of America, it's political malpractice," Costello tweeted.

We all know challenges of suburban R's. The bloc of competitive R held districts less impacted by POTUS thus far are those w high # of immigrants. So now POTUS, out of nowhere, brings birthright citizenship up. Besides being basic tenet of America, it's political malpractice. — Ryan Costello (@RyanCostello) October 30, 2018

But there was also evidence that Trump's hardline focus on immigration was increasing the pressure on some Democrats trying to cling to Senate seats in red states.

Democratic Sen. Claire McCaskill of Missouri ventured into Trump's territory on Fox News on Monday to say: "I do not want our borders overrun. And I support the President's efforts to make sure they're not."

Democrats have responded to Trump's broadsides by largely sticking to campaign themes of expanding health care coverage and protecting popular programs like Medicare, Medicaid and Social Security.

But some of the party's potential contenders for the 2020 presidential race, which will erupt as soon as the midterm elections are over, have used the midterms to put down early markers in key primary states.

Former Vice President Joe Biden, for instance, was in Wisconsin on Tuesday, a state that Trump often crows he snatched from the Democrats in his surprise win over Hillary Clinton two years ago.

"I am sick and tired of this administration. I am sick and tired of what's going on," Biden said, expanding the Democratic election strategy into a broader argument on the need to curtail the Trump presidency.

"I'm sick and tired of being sick and tired, and I hope you are too."