American cartel watchdogs have had eventful weeks.

In December, the competition authority FTC filed a lawsuit to prevent the software company Microsoft from buying the video game manufacturer Activision for almost 70 billion dollars.

She has thus started what is probably the most spectacular cartel case since Joe Biden has been US President.

However, it is far from the only notable competition dispute.

On the same day that the Microsoft lawsuit came, court proceedings began over an acquisition of the Facebook parent company Meta, which the FTC also wants to thwart.

And just a few weeks earlier, the Justice Department, the country's second most authoritative antitrust authority, landed a major success.

The book division of the Bertelsmann group gave up its plans for a multi-billion dollar acquisition of an American competitor against which the ministry had filed a lawsuit.

All of these cases are to be understood as indications that the antitrust authorities have become significantly more aggressive under Biden.

It is all the more striking what a contrasting program the Congress in Washington is delivering.

Because as busy as the antitrust authorities are, the legislators are inactive.

Attempts to tighten competition law have so far failed.

Since Biden took office, there have been a whole series of bills that have been widely announced and have been well received by politicians from both parties.

But just before Christmas, two of these initiatives, which posed a significant threat to tech giants like Apple, Google or Amazon, were scrapped for the time being.

They were at times planned as part of a larger budget package, but were then scrapped almost at the last moment.

These were projects that are in a similar form building blocks of the new EU law for digital markets (DMA), but are not being implemented in the USA for the time being.

Broader understanding of market dominance

The antitrust authorities can therefore not count on support from Congress.

That doesn't change much in terms of their aggressiveness, in fact they are particularly determined at the moment to exhaust the leeway that the applicable competition law gives them.

Not only have they filed a comparatively large number of lawsuits since Biden took office in order to bring merger projects to failure.

In doing so, you have repeatedly entered unfamiliar territory.

For example, with their intervention against Meta's acquisition of Within, a provider of a popular fitness app.

It's a relatively small transaction that would probably have been waved through earlier.

A broader understanding of market dominance is currently being expressed in many antitrust lawsuits.

Traditionally, concerns about higher consumer prices have often been cited.

Now arguments are also being made about possible harmful consequences for employees or innovations in a market.

The Justice Ministry justified its lawsuit against the purchase of a book publisher agreed by Bertelsmann with the fact that the advances paid to authors could decrease.

Despite its size, Microsoft's takeover of Activision is not a crystal-clear candidate for an antitrust lawsuit.

It is essentially a so-called vertical merger, since the companies compete directly with each other to a limited extent.

A deliberate confrontational course

The increased confrontational course is what the White House wants, Biden has filled the leading positions in the competition authorities with prominent critics of American tech giants, such as Lina Khan, who heads the FTC.

Admittedly, their harder line entails an increased risk of losing antitrust disputes in court.

In fact, a whole series of lawsuits have failed, and the prospects of success in the lawsuit against Microsoft are also considered uncertain.

The more defeats there are, the higher the hurdles for further lawsuits could become in the future.

But the authorities appear to be willing to take that risk, and FTC chief Khan has indicated she can find some good in failure.

Because this could show Congress how urgent it is to revise the antitrust laws.

However, this is not to be expected in the near future.

From now on, power in Congress is again divided in two, because the Republicans take over the majority in the House of Representatives.

Although there is also sympathy in their ranks for stricter antitrust laws, they should have other priorities for the time being.

The antitrust authorities will have to fight their battle alone for the foreseeable future.