The two parties displayed their divisions with nearly every punchline in President Donald Trump's State of the Union address. Republican lawmakers applauded; Democrats did not.

Yet in a subtler way, the speech also underscored disagreements within his party. And those internal splits, as much as Democratic resistance, explain why enactment of major new initiatives in 2018 appears unlikely.

The fault line within Trump's GOP separates the party's growing constituency among white working-class voters from more-affluent, pro-business supporters. Trump and Republican congressional leaders champion the economic interests of the latter.

The president's speech gave voice to that advocacy when he touted his "massive tax cuts" for corporations and individuals, reductions in business regulation and financial market gains that have boosted the value of stock portfolios. The bulk of those benefits flow to the upper-income Americans who own and operate those businesses.

And his remarks were encouragingly silent on at least one topic that worries those pro-business Republicans. While Trump called for improving international trade deals to make them more favorable to the U.S., he did not repeat past threats to renounce the North American Free Trade Agreement with Canada and Mexico, which corporate leaders do not want to scuttle.

To be sure, the president also hailed benefits the tax cut provides for families with modest incomes through lower rates, a higher standard deduction and an increased credit. But those benefits are small by comparison, and tepid public support shows that Americans know it; in the most recent NBC News/Wall Street Journal poll, a 51 peprcent majority of blue-collar whites said they believe the new law will either raise their taxes or keep them the same.

As with business leaders, the speech was encouragingly silent on a key issue for working-class Republicans, too. The president did not invoke the need for curbing the Social Security and Medicare benefits they depend on. Without his support, GOP congressional leaders can't enact major "entitlement reform" they and business leaders consider vital to shrinking the government's bills.

Trump pledged to curb the high prescription prices that deplete working-class wallets. But he has offered that pledge since his 2016 campaign, and the absence of specific action against them in the speech casts doubt on the likelihood of an effective initiative.

In the same vein, Trump's promises of major job-training programs, paid family leave, infrastructure development and action on the opioid crisis ravaging blue-collar communities show no sign of moving beyond rhetorical outreach. Those priorities cost money that Republican congressional leaders don't want to spend, especially now that the tax cut has placed the federal budget on a path back to trillion-dollar deficits by next year.

Trump did, however, offer his blue-collar supporters something that research has shown they value: affirmation of their identities and status as white Christians in a nation that continues to grow more diverse by race, religion and country of origin.

They got it when the president invoked God, when he asserted the reasons "why we salute our flag, why we put our hands on our hearts for the Pledge of Allegiance, and why we proudly stand for the national anthem." The last drew a contrast with African-American athletes who have knelt during "The Star-Spangled Banner" to protest racial injustice.

They got it when he vowed new policies to protect them from immigrants he said have poured across America's southern border committing "savage" crimes. He assailed immigrant gang members as Democrats seek legislative protection for Latino "dreamers" brought illegally to the U.S. as children.

They got it when he vowed to cut foreign aid — a tiny part of the federal budget — to "enemies of America." That came a few days after he derided "s---hole" countries in Africa and the Caribbean in a meeting with senators.

Facing rising accusations of racism, the president boasted that African-American unemployment has dropped to its lowest-ever level under his administration. He said it with an edge.

Of course, the identity politics that matter most to this president involve his own identity. Echoing his 2016 theme that "I alone can fix" America's problems, he claimed unique success for his economic and anti-ISIS policies even though they have largely sustained trends or strategies he inherited from President Barack Obama.

With a hint of self-protection, the president who assails the Justice Department "witch-hunt" asked Congress to let his administration remove employees "who undermine the public trust or fail the American people."

Will Republican lawmakers fulfill his wishes on the Russia investigation? Perhaps they will.

In the Journal/NBC poll, 28 percent of Republicans joined overwhelming majorities of Democrats and independents in rating "personal and ethical standards" as poor. But 78 percent of them continue to support his performance as president.