The trial to decide whether to remove U.S. President Donald Trump from office began this week. Trump is charged with abusing his power as president, and with obstructing, or blocking, Congress during its investigation. Lawmakers in the Senate will hear arguments both for and against removal. Seven lawmakers from the House of Representatives are making the argument for removing Trump from office. They are all Democrats. Trump is a Republican. Those Democrats say Trump abused the power of his office by urging the president of Ukraine to investigate a political rival. During that time, Trump was withholding hundreds of millions of dollars in military aid to Ukraine. The Democrats say Trump was inviting a foreign country to interfere in American politics. And, they say, his request served his own political interests instead of the national security interests of the country.