Trump bombs Syria, demotes Steve Bannon and gets a Supreme Court nominee confirmed. Highlights of Week 11.

Reporting from Washington  â€”  Just one week ago, Secretary of State Rex Tillerson, speaking in Turkey, made official a policy shift that President Trump had hinted at since early in his campaign — the U.S. would no longer actively seek the ouster of Syrian President Bashar Assad.

Four days later, Assad’s forces, according to U.S. intelligence, launched a sarin-gas attack on a rebel-controlled town in northern Syria. And on Thursday, in retaliation, American missiles rained down on a Syrian airfield.

It was the first direct U.S. strike against Assad’s forces in the seven-year history of that country’s civil war.

Good afternoon, I’m David Lauter, Washington bureau chief. Welcome to the Friday edition of our Essential Politics newsletter, in which we look at the events of the week in Washington and elsewhere in national politics and highlight some particularly insightful stories.

AN OVERSHADOWED SUMMIT

We can’t know yet how this attack ultimately will be seen. Will it be as a successful effort at deterrence — a low-cost military strike efficiently executed by the president, Defense Secretary James N. Mattis and national security advisor H.R. McMaster?

Or will we look back at Thursday evening as the moment Trump took a fateful first step into Syria’s intractable civil war and had to give up on warmer relations with Russia? By Friday morning, Syria was denouncing the attack as aggression, and Russia was vowing to strengthen Syria’s air defenses.

What we do know is that the 11th week of Trump’s presidency marked the point at which he ran up against the harsh realities of a complex world.

The week was supposed to be all about Trump’s meeting at Mar-a-Lago with Chinese President Xi Jinping and the successful confirmation of the president’s Supreme Court nominee, Neil M. Gorsuch.

But events intervened in an unusually brutal fashion.

The administration initially had a muted response to Syria’s chemical weapons attack, as Bill Hennigan, Nabih Bulos and I reported. White House Press Secretary Sean Spicer, speaking off camera, denounced the use of chemical weapons as “heinous� but pointedly noted that the administration was not interested in regime change. Assad’s hold on power was a “political reality,� he said.

That was consistent with Trump’s “America First� policy of not engaging in moral crusades elsewhere in the world. It was also consistent with Trump’s own repeatedly tweeted advice to President Obama the last time Syria used chemical weapons.

At the time, in roughly a dozen tweets in late August and early September, Trump bluntly warned Obama not to launch an airstrike in retaliation.

One example: “Don’t attack Syria - an attack that will bring nothing but trouble for the U.S. Focus on making our country strong and great again!�

But the world looks different from the Oval Office, as Obama repeatedly said. The pictures of dying children had a strong effect on Trump, according to people who talked with him.

By the next day, in a news conference with the visiting King Abdullah of Jordan, Trump publicly said that the attack “crosses many, many lines� and had changed the way he thought about Assad.

By that night, the Pentagon had drawn up options, and on Thursday Mattis flew to Florida to give Trump a final briefing.

A CROWDED AGENDA

At the same time they were grappling with Syria, Trump’s advisors were trying to come up with a policy to handle the more existential threat posed by North Korea’s nuclear program — a main item on the agenda for the summit with Xi.

The subject is one where Trump’s tough talk will be put to the test, Barbara Demick reported.

In advance of the summit, Trump advisors expressed hopes that he and Xi could form a personal bond, Brian Bennett, Noah Bierman and Mike Memoli reported. China experts warned that was unlikely.

Chinese officials mostly expressed anxieties about what could go wrong, our colleague Jonathan Kaiman reported from Beijing.

Unlike previous U.S.-Chinese summit meetings, this one was not tightly choreographed in advance, White House officials said.

That doesn’t mean the agenda was simple, though.

In the run-up to the summit, both the U.S. and the North Korea have escalated tensions. Pyongyang has launched a series of provocative missile tests. Administration officials, especially Tillerson, who traveled to the region recently, have conspicuously rattled sabers.

The rhetoric has been designed, in part, to warn the Chinese that if they don’t do more to restrain the North Koreans, the U.S. might take military action.

In addition to North Korea, Trump talked publicly about wanting to have a tough conversation with Xi about trade. One problem, however, is that on North Korea and trade, Trump wants concessions from China. It’s not clear what, if anything, he’s prepared to offer in return.

Another problem is that China has tools for leverage. One of the few big accomplishments in U.S.-Chinese relations in the last few years, for example, was an agreement under which the Chinese cut back sharply on industrial cyber-espionage aimed at U.S. firms. In advance of the summit, U.S. cyber experts warned those gains could be reversed, Bennett reported.

One issue that’s not expected to get a lot of attention is climate change. Under Obama, the U.S. used to push China on global warming. Now the positions have been reversed, Kaiman reported. The Chinese will continue to try to reduce the amount of coal they burn — something they desperately need to do to clean up the smog that chokes northern China’s cities. But whether China can, or is willing to, step into an international leadership role on the issue is a big unknown.

Another issue likely to be little mentioned — human rights. As Tracy Wilkinson reported, that topic has faded quickly in the Trump era.

A RESHUFFLE OR A SHAKEUP?

As Trump prepared for the meeting with Xi, he reorganized his National Security Council, removing his political strategist Steve Bannon.

As Bennett, Bierman and Memoli noted, the move “largely brings a traditional structure back to a White House national security system that has been roiled by leaks, infighting and intrigue since Trump took office.� It also strengthened the authority of McMaster, who has pushed to rid the national security staff of political ties.

What the move meant for Bannon was less clear. His allies insisted that no demotion was implied. His enemies posited the opposite — that Trump had grown annoyed at being portrayed as Bannon’s puppet, that his influential son-in-law Jared Kushner had arranged to take Bannon down a peg, that within the White House, Bannon had taken the blame for much that has gone wrong the last 11 weeks.

One of the most conspicuous of those failures, in which Bannon was heavily involved, was the effort to repeal and replace Obamacare. As Lisa Mascaro and Noam Levey reported, White House officials and congressional Republicans spent much of the week trying to resuscitate their effort to pass a new healthcare law. By week’s end, Congress left town for a two-week recess having made no visible progress.

A CHANGED SENATE

Amid the storms, one of Trump’s initiatives — the Supreme Court nomination of Neil M. Gorsuch — moved steadily forward. Friday morning, he won a seat on the high court, by 54-45.

To get to the goal, Republicans had to invoke the so-called nuclear option — changing the Senate’s rules — to overcome Democrats’ filibuster of Gorsuch.

But Democratic hopes that they could make the GOP pay a heavy political price either for the nomination itself or for the rules change never panned out. Unlike healthcare or other nominations, notably that of Education Secretary Betsy DeVos, polls consistently showed that conservatives cared more about the court fight than liberals did.

That’s been true for years, and probably reflects liberals being reasonably satisfied with the status quo on the high court, even though five of its nine members are Republican appointees. In recent years, for example, the court has legalized same-sex marriage nationwide and struck down state laws that sought to drive abortion providers out of business.

Conservatives, by contrast, have tried for years to get justices on the Supreme Court who would push the country in the other direction.

That dynamic could change the next time a seat comes open — if one of the court’s liberal justices or the bench’s swing vote, Justice Anthony M. Kennedy, steps down.

Meantime, the fight over Gorsuch and the rules change further strained relations in the Senate. Under the pressures of a highly partisan age, the Senate has steadily become more like the House. In advance of this week’s votes, Mascaro looked at the question: Will the fight over the filibuster break the Senate?

Lost in all the Senate jargon? Mascaro did this useful Q&A on filibusters, cloture motions and what the nuclear option means the future of the Senate.

TRUMP’S TWEET CLAIMS ANOTHER VICTIM

Trump’s now infamous tweet in which he claimed that Obama had wiretapped him in Trump Tower — a charge made without evidence and denied by law enforcement, Republican congressional leaders and pretty much anyone else who might know — has proved deeply costly to the White House.

In defense of the boss’ tweet, administration officials have gone through multiple contortions. The most striking was the decision last month to have House Intelligence Committee Chairman Devin Nunes (R-Tulare) surreptitiously come to the White House, view ambiguous intelligence reports, then make a public show of rushing to the Oval Office to brief Trump about newly discovered evidence that didn’t support his claim but could be made to sound like it kind of might have.

That stunt brought the Intelligence Committee’s work to a standstill. Thursday, it became even more costly, as the House Ethics Committee announced that it was investigating whether Nunes had improperly disclosed classified information. Nunes announced that he was stepping aside, and as David Cloud reported, there were clear signs that Speaker Paul Ryan (R-Wis.) had pushed him to do so.

If you haven’t already done so, read Cathy Decker’s terrific profile of the two worlds of Devin Nunes — revered at home, increasingly doubted in Washington.

And don’t miss the companion piece, Sarah D. Wire’s also excellent profile of Rep. Adam Schiff (D-Burbank), Trump’s public prosecutor.

ALL THE PRESIDENT’S TWEETS

Meantime, speaking of Trump’s tweets: We’re compiling all of them. It’s a great resource. Take a look.

SOME FINAL, NOTABLE PIECES

As the Trump administration continues its efforts to undo the environmental policies of the last couple of decades, just going to work at the EPA can be an act of defiance, Evan Halper wrote.

Homeland Security Secretary John Kelly said officially what administration officials have previously whispered: There’s not going to be a border wall from “sea to shining sea.� The administration will build new fortifications, mostly fences, not walls, in some areas, but not everywhere, Kelly testified.

In an interview here in our Washington bureau, Sen. Kamala Harris had some interesting observations about Democratic resistance to Trump and the party’s path out of the wilderness. As Halper noted, some of what she said flies against her public image.

The Justice Department announced it was reconsidering agreements with police departments over use of force. Civil rights groups found that prospect unsettling, Del Quentin Wilber reported.

And, finally, Arnold Schwarzenegger has been taking jabs at Trump, who has been punching back. Seema Mehta has been following the action.

LOGISTICS

That wraps up this week. My colleague Sarah D. Wire will be back Monday with the weekday edition of Essential Politics. Until then, keep track of all the developments in national politics and the Trump administration with our Essential Washington blog, at our Politics page and on Twitter @latimespolitics.

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@davidlauter