When the Senate voted 68 to 32 in June to pass the United States Innovation and Competitiveness Act, a Bill aimed at boosting American innovation to compete with China, the vote margin - overwhelmingly bipartisan by Capitol Hill's standards - was read as a signal of how countering Beijing had become the rarest of unicorns in Washington.

It was an issue on which both Democrats and Republicans agreed.

The Bill is part of a record-breaking deluge of China-related legislation in recent years, coming from both Republicans and Democrats, reflecting how interest in China is at an all-time high, and how robust the bipartisan consensus behind getting tough on China is.

This, in part, explains why America's confrontational relationship with China has endured a change in presidents.

Yet this unity of purpose is not carte blanche for Washington to do whatever it likes in confronting China.

Beneath the surface are plenty of forces and diverging interests that complicate matters, and nuance that might get lost when looking at the overall consensus. Some are the result of America's own institutional checks and balances, while others are differences between political parties and business groups.

Familiarity with these internal divisions helps in understanding how America confronts China, and how fast and how aggressively - even if at the end of the day, its confrontational attitude does not change.

A spike in bills on China

America is seeing an unprecedented number of Bills in Congress that are aimed at China - not just a recent high but at least a three-decade high, Ms Anna Ashton, the vice-president of global affairs at the US-China Business Council, told The Straits Times.

According to the council's tracking, at least 317 China-related legislative proposals have been introduced since the start of the 117th Congress in January this year.

This puts it on track to exceed the volume of such legislation introduced by the previous 116th Congress, which had a total of 552 China-related proposals in the two years before.

The 116th Congress had already broken records. Its China legislation was more than double that of any Congress going back to 1983, when the tracker's records began, and in most cases it was three or more times higher.

This far outstripped China-related legislation in the wake of the Tiananmen Square crackdown from 1989 to 1990, and around the time that China was granted permanent normal trade relations status, from 1999 to 2000, said Ms Ashton.

"Many Bills have bipartisan backing," she said, adding that in the last Congress, the main proposers of China-related legislation in the House and Senate were around 60 per cent Republican and 40 per cent Democrat. "There's plenty from both parties."

This surge is significant because even though most do not become law, they can have an effect on what eventually does - parts of Bills may get incorporated into other legislation, for instance.

They also signal "a growing desire among members of Congress to be involved in the China debate", said American Enterprise Institute senior fellow Zack Cooper.

There is also an element of point-scoring behind this level of activism on China policy.

"Basically, it's a form of political virtue signalling," said Dr Jiakun Jack Zhang, an assistant professor of political science at the University of Kansas.

In a recent paper, he and a graduate student, Mr Spencer Shanks, found that senators with presidential aspirations were more likely to sponsor anti-China Bills, a behaviour seen in both parties but more so among Republicans.

"'Tough on China' is an ideal issue for senators trying to advance their future political careers. It is a high-profile foreign policy position that benefits from the cover of bipartisan support, with no immediate consequences to the sponsoring senator," said Dr Zhang.

Internal processes

While that calculus may accelerate confrontation with China, one complicating factor - and a bit of a brake on the process - is America's congressional processes.

Firstly, both the House and the Senate must pass the Bill before the president can sign it into law.

If one chamber passes the Bill but the other does not, then it does not move forward - which is currently happening with the Innovation and Competitiveness Act, which has stalled in the House.

Politico reported last Monday that the House is advancing separate provisions of the Senate's Bill in different committees, a complicating factor that slows down the whole process.

Secondly, just because a Bill is passed does not mean money will flow.

America has separate processes for authorisation and appropriation. Authorisation committees, like the Senate's armed services and foreign relations committees and the House's foreign affairs committee, help craft the laws that establish federal programmes. But appropriation committees greenlight the budget for these programmes, acting independently.

"You can be authorised to spend however much money you want on something, but unless you actually have that money appropriated, it doesn't really change anything," said Dr Cooper.

In practice, appropriations committees - the ones doing the actual budgets - tend to have less Asia expertise than authorisation committees, he said.

"So you get legislation that sounds very good, but maybe doesn't have full funding," he said. "A challenge that we've had over the last five or 10 years when it comes to Asia issues is the authorising committees have supported some initiative, but the appropriations committees haven't really wanted to put real money into it."

One example is the Pacific Deterrence Initiative (PDI), which was established in last year's National Defence Authorisation Act to boost US military preparedness in the Indo-Pacific. But while US$5 billion (S$6.7 billion) was requested for the PDI, appropriators have not fully funded it yet, with negotiations behind the scenes in Congress still ongoing.

Republicans, Democrats and businesses

While there is robust agreement between Republicans and Democrats on the need to counter China, there are also some differences in their approaches.

"Sometimes you hear Democrats talk more about the United States needing to run faster, whereas some Republicans talk a bit more openly about perhaps trying to slow China down," said Dr Cooper.

Republicans also tend to focus more on the military dimension of the US-China competition, while Democrats are more likely to zoom in on the ideological aspects, such as democracy and human rights issues.

Within the Biden administration, officials also have different opinions on advancing a trade strategy with Asia, said Dr Cooper.

"Asia experts believe that the US needs a trade and economic strategy in Asia to be successful. But the political experts don't believe that is attractive with most of the American people," he said.

But overall, these variations on approaches to China are relatively small.

The larger division - relatively speaking - may be between business groups on one hand, and Congress and the White House on the other.

Multinational corporations, once the champion of engagement with China, "become increasingly pessimistic about the business climate in China and increasingly vocal critics of Chinese industrial policy", said Dr Zhang.

This shift in business sentiment meant that on the whole, the business community was not too vocally opposed to the Trump administration confronting China.

But in recent months, corporations have also been worried that proposed laws that would crack down on China's human rights abuses are too restrictive and bad for business.

Last November, The New York Times reported that big companies such as Nike, Coca-Cola and Apple were lobbying against Bills banning products tied to forced labour in Xinjiang.

Congresswoman Jennifer Wexton of Virginia, who introduced one of the Bills in the House, slammed corporate lobbyists for trying to water down the proposed enforcement provisions, telling the Canadian Broadcasting Corporation: "They're going behind the scenes and trying to change the law... it's going to impact their supply chains and make it harder for them to profit off of this forced labour."

Net effect

These internal divisions can help the US at times, giving the Biden administration leverage against Beijing to press for change.

"The White House tends to be more engaged in bilateral negotiations with Beijing, whereas the Congress is often passing legislation that's putting pressure on China. It's good cop, bad cop," said Dr Cooper.

But it can also be a disadvantage, with divisions between the White House and the Congress about what the US should be doing in the region complicating matters.

On the flip side, others also worry that the bipartisan consensus may increase the risk of groupthink that could lead to foreign policy blunders or overreach, like what happened with the invasion of Iraq in 2003.

"The US has legitimate concerns with the rise of China, just as it had cause to act in the wake of 9/11, but it did not think through the consequences of actions taken hastily," said Dr Zhang.

He added: "The danger of bipartisanship on a complex issue that requires deliberation is that sceptics are afraid to speak up, dissenting voices are sidelined, and the White House has less room to manoeuvre for fear of Congressional backlash.

"I believe a healthy political debate about the issues is important to make sure that US policy response to China is calibrated and effective."

For now, both political parties are fairly united in confronting China. But while America is a behemoth, it is not a monolith - and understanding the extent of the bipartisan consensus is crucial to know where things stand, instead of seeing them as mixed signals.