The House is preparing to vote Thursday on a war powers resolution to halt President Donald Trump's attack on Iran, a sign of unease in Congress over the rapidly widening conflict that is reordering U.S. priorities at home and abroad.

It's the second vote in as many days, after the Senate defeated a similar measure along party lines. Lawmakers are confronting the sudden reality of representing the American people in wartime and all that entails — with lives lost, dollars spent and alliances tested by a president's unilateral decision to go to war with Iran.

The tally in the House is expected to be tight, but the outcome will provide an early snapshot of the political support, or opposition, to the U.S.-Israel military operation and Trump's rationale for bypassing Congress, which alone has the power to declare war.

"Donald Trump is not a king, and if he believes the war with Iran is in our national interest, then he must come to Congress and make the case," said Rep. Gregory Meeks, the top Democrat on the House Foreign Affairs Committee.

Meeks said in his nearly three decades in Congress, the hardest votes he has taken have been deciding whether to send U.S. troops to war.

The roll calls are a clarifying moment for the president and the parties just days into the overseas conflict that has quickly carried echoes of the long U.S. wars in Afghanistan and Iraq. Many veterans of those wars have since run for office and now serve in Congress.

Trump's Republican Party, which narrowly controls the House and Senate, largely sees the conflict with Iran not as the start of a new war, but the end of a regime that for decades has long menaced the West. The operation has killed Iran's Supreme Leader Ayatollah Ali Khamenei, which some view as an opportunity for regime change, though others warn of a chaotic power vacuum.

Rep. Brian Mast of Florida, the GOP chairman of the House Foreign Affairs Committee, publicly thanked Trump for taking action against Iran, saying the president is using his own constitutional authority to defend the U.S. against the "imminent threat" the country posed.

Mast, an Army veteran who worked as a bomb disposal expert in Afghanistan, said the war powers resolution was effectively asking "that the president do nothing."

For Democrats, Trump's war with Iran, influenced by Israeli Prime Minister Benjamin Netanyahu, is a war of choice that is testing the balance of powers in the U.S. Constitution.

"The framers weren't fooling around," said Rep. Jamie Raskin, D-Md., arguing that the Constitution is clear that only Congress can decide matters of war.

He said whether lawmakers support or oppose the Trump administration's military action, they should have the debate. "It's up to us, we've got to vote on it."

While views in Congress are largely falling along party lines, there are crossover coalitions. Both the House and Senate resolutions were bipartisan, and are drawing bipartisan support and opposition. The House is also voting on a separate resolution affirming that Iran is the largest state sponsor of terrorism.

The war powers resolution, if signed into law, would immediately halt Trump's ability to conduct the war unless Congress approved the military action. The president would likely veto the measure.

As an alternative, a small group of Democrats has proposed a separate war powers resolution that would allow the president to continue the war for 30 days before he must seek congressional approval. It is not expected to come yet for a vote.

After launching a surprise attack against Iran on Saturday, Trump has scrambled to win support for a conflict that Americans of all political persuasions were already wary of entering. Trump administration officials spent hours behind closed doors on Capitol Hill this week trying to reassure lawmakers that they have the situation under control.

Six U.S. military members were killed over the weekend in a drone strike in Kuwait, and Trump has said more Americans could die. Thousands of Americans abroad have scrambled for flights, many lighting up the phone lines at congressional offices as they sought help trying to flee the Middle East.

Defense Secretary Pete Hegseth said that the war could extend eight weeks, twice as long as the president first estimated. Trump has left open the possibility of sending U.S. troops into what has largely been a bombing campaign by air. Hundreds of people in the region have died.

The administration said the goal is to destroy Iran's ballistic missiles that it believes are shielding its nuclear program. It has also said Israel was ready to act against Iran, and American bases would face retaliation if the U.S. did not strike first. On Wednesday, the U.S. said it torpedoed an Iranian warship near Sri Lanka.

The Supreme Court cleared the way Monday for California schools to tell parents if their children identify as transgender without getting the student's approval, granting an emergency appeal from a conservative legal group.

The order blocks for now a state law that bans automatic parental notification requirements if students change their pronouns or gender expression at school.

The split decision comes after religious parents and educators challenged California school policies aimed at preventing schools from outing students to their families. Two sets of Catholic parents represented by the Thomas More Society say it caused schools to mislead them and secretly facilitate the children's social transition despite their objections.

California, on the other hand, argued that students have the right to privacy about their gender expression, especially if they fear rejection from their families. The state said that school policies and state law are aimed at striking a balance with parents' rights.

The high court majority, though, sided with the parents and reinstated a lower-court order blocking the law and school policies while the case continues to play out.

"The parents who assert a free exercise claim have sincere religious beliefs about sex and gender, and they feel a religious obligation to raise their children in accordance with those beliefs. California's policies violate those beliefs," and burden the free exercise of religion, the majority wrote in an unsigned order.

The court's three liberal justices publicly dissented, saying the case is still working its way through lower courts and there was no need to step in now. "If nothing else, this Court owes it to a sovereign State to avoid throwing over its policies in a slapdash way, if the Court can provide normal procedures. And throwing over a State's policy is what the Court does today," Justice Elena Kagan wrote.

Conservative Justices Samuel Alito and Clarence Thomas, meanwhile, noted they would have gone further and granted teachers' appeal to lift restrictions for them.

The Thomas More Society called the decision "the most significant parental rights ruling in a generation."

California Gov. Gavin Newsom's office defended the law, saying teachers should be focused on instruction, not required "to be gender cops."

The order "undermines student privacy and the ability to learn in a safe and supportive classroom, free from discrimination based on gender identity," said Marissa Saldivar, a spokesperson for the Democratic governor.

The Supreme Court has ruled for religious plaintiffs in other recent cases, including allowing parents to pull their children from public-school lessons if they object to storybooks with LGBTQ+ characters.

The California order comes months after the court upheld state bans on gender-identity-related healthcare for minors. The justices also seem to be leaning toward allowing states to ban transgender athletes from playing on girls sports teams.

School policies for transgender students, meanwhile, have also been on the court's radar in other cases. The court rebuffed another similar case out of Wisconsin in December, but three conservative justices indicated they would have heard the case. Justice Samuel Alito called the school policies "an issue of great and growing national importance."

The justices have been weighing whether to hear arguments in cases out of states like Massachusetts and Florida filed by other parents who say schools facilitated social transition without informing them.

The Trump administration, meanwhile, found in January that California's policies violated parents' right to access their children's education records. The Justice Department also sued after determining the states' transgender athlete policies violate federal civil rights law.