The Vanguard US Total Market Shares Index ETF (ASX: VTS) fell another 3% today, marking another tough day for the exchange-traded fund (ETF). This means it's now down over 10% since the end of January 2025 as tariff worries grow.

Investors seem to be increasingly worried about the trade war that's growing between the US and a number of countries, including Canada, China, Mexico, the European Union (EU) and so on.

Trump's second term has certainly started with a lot of headlines and volatility.

Let's look at what's shaking the market right now and whether it's time to buy the VTS ETF.

Tariff troubles

It has been widely reported by various media outlets, including AP News, that President Trump plans to roll out another group of tariffs to "free the United States from foreign goods".

AP News also reported that Trump is inviting CEOs to the White House to commit to investing hundreds of billions of dollars in new projects to avoid the import taxes. The idea is that the reciprocal tariffs would match the rates charged by other countries and take subsidies into account. Countries like the EU, South Korea, Brazil and India could be among the targets.

Trump said:

This is the beginning of Liberation Day in America. We're going to charge countries for doing business in our country and taking our jobs, taking our wealth, taking a lot of things that they've been taking over the years. They've taken so much out of our country, friend and foe. And, frankly, friend has been oftentimes much worse than foe.

When asked in an interview with NBC News about car prices increasing, Trump said:

I hope they raise their prices, because if they do, people are gonna buy American-made cars. I couldn't care less because if the prices on foreign cars go up, they're going to buy American cars.

This has given VTS ETF investors, and the wider market, something (else) to worry about.

Is this a good time to invest in the VTS ETF?

The Vanguard US Total Market Shares Index ETF is cheaper, but there are plenty of stocks that also are down.

The diversification of the VTS ETF is advantageous at a time like this. It's heavily diversified with thousands of holdings, so it can reduce risk if a certain sector goes through particular pain.

I like that we can use this fund to gain exposure to some of the world's strongest businesses including Apple, Microsoft, Nvidia, Amazon.com, Alphabet, Meta Platforms, Tesla, Broadcom, and Berkshire Hathaway. Plus, gaining this allocation comes with an annual management fee of just 0.03%, which is very, very cheap.

While I don't know what share prices are going to do in the coming months and years, but I do see a more appealing valuation.

It's at times like this that one of the most famous pieces of investment advice is useful:

Be fearful when others are greedy and greedy when others are fearful.

It seems like we're approaching another level of uncertainty, so it could be a good time to invest. If the VTS ETF fell even further, then I'd say it'd be an even better investment.