"Our Mann in America" is a weekly column discussing the big talking points in the U.S. for an international audience. Jonathan Mann is an anchor for CNN International and the host of Political Mann.
(CNN) -- This week Washington went to war.
Lawmakers who were elected back in November officially entered Congress, with the new Republican majority in the House of Representatives gunning immediately for President Barack Obama's signal achievement - the overhaul of the U.S. healthcare system.
"I and a lot of my fellow freshmen ran on repealing Obamacare," said Republican Congressman Joe Walsh. "The folks in my district told me month after month they wanted this thing repealed."
The health plan aims to provide medical insurance to nearly all Americans. Republicans consider it a complicated and costly burden on the country -- but their battle to kill it probably won't draw blood.
They do control the House and have scheduled a repeal vote for Wednesday. But the Senate and White House remain in Democratic hands. No law can be passed or repealed without their approval.
Obama suggests that the Republicans will simply try to impress their supporters with the effort and then abandon it
"I think that there's going to be politics," he said. "That's what happens in Washington."
But the Republicans have other ways to oppose and annoy the administration.
In the weeks to come, they plan a wide range of investigations, exercising American lawmakers' traditional role overseeing government operations, with the traditional accompanying opportunities to embarrass the party in power.
One committee of House lawmakers has already announced plans for public hearings on no less than six separate issues. There's no telling how many more committees will come forward with their own ambitious agendas.
But the biggest minefield of all could be a vote on whether the U.S. government can keep borrowing money above its currently approved "debt ceiling."
The Congress has only authorized total borrowing of up to $14.3 trillion. The government's mounting debts are already approaching $14 trillion and will grow more in the months to come.
Republicans who want to shrink the government and reduce its spending have suggested they'd vote against additional borrowing.
Administration officials say the unprecedented prospect of Washington running out of money would rattle financial markets worldwide.
The Republicans and Democrats can obviously avoid conflict if they want to.
But the prospects aren't entirely promising. It does look like war -- and the shooting is about to begin.