1. Explosive politics: US stock futures were lower following a day of major political developments.

President Donald Trump's former campaign chairman Paul Manafort was found guilty on eight counts of financial crimes. Within the hour, Trump's former lawyer Michael Cohen plead guilty to multiple counts of campaign finance violations, tax fraud and bank fraud.

Cohen said that he had acted "in coordination and at the direction of a candidate for federal office."

Strategists warn that the developments could preoccupy the White House and hurt market confidence.

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"The greatest risk to markets and business environments is a loss in confidence pertaining to the Trump administration's ability to govern," said analysts at Eurasia Group.

2. US-China trade talks: The trade war between the United States and China is at a turning point on Wednesday as both sides meet in Washington.

There's hope that new talks could lead to an easing of tensions.

But President Donald Trump said he does not "anticipate much" from the discussion, according to an interview with Reuters on Monday.

The United States stands ready to place a 25% tariff on another $16 billion of Chinese goods starting on Thursday. China is expected to respond with a 25% tariff on an equal amount of American goods.

This would be the second round of tariffs imposed by the two countries this year. Some $50 billion of goods on each side could be taxed as of Thursday.

3. Stocks power on: The bull market that began in March 2009 makes history on Wednesday for being 3,453 days old — the longest period of uninterrupted gains in US history.

The S&P 500 hit a low of 666.79 during the Great Recession. On Tuesday, it hit an all-time high at 2,873.23.

The S&P 500 is up 7.1% so far in 2018. The Nasdaq has surged by nearly 14% over the same time period. The Dow Jones industrial average has lagged with a gain of 4.5%.

European markets were little changed in early trading. Asian markets ended the day mixed.

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4. Earnings and economics: Lowe's (LOW) and Target (TGT) will release earnings before the open. L Brands (LB) and Williams-Sonoma (WSM) will follow after the close.

Shares in La-Z-Boy (LZB) surged 20% premarket after the firm reported better-than-expected quarterly results.

The Federal Reserve will release minutes from its August meeting on Wednesday at 2 p.m. ET. Investors will watch closely for signals about the Fed's response to the intensifying trade issues between the United States and several other countries.

In an interview with Reuters earlier this week, Trump said he is "not thrilled" with Chairman Jerome Powell for raising interest rates, arguing the central bank should do more to help the US economy.

The National Association of Realtors is set to report data on existing US home sales from July at 10 a.m. Sales have been sluggish over the past few months because of high home prices, which might be turning off some potential buyers.

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5. Coming this week:

Wednesday — Target (TGT), Lowe's (LOW) and L Brands (LB) earnings
Thursday — Alibaba (BABA), HP (HPQ), Ross Stores (ROST) and Gap (GPS) earnings, US tariffs on 279 Chinese products take effect
Friday — Foot Locker (FL)earnings, Federal Reserve chairman Jerome Powell speaks at the Economic Policy Symposium in Jackson Hole