As the House of Representatives prepares to vote on a resolution of disapproval against Donald Trump’s declaration of a “state of emergency,” not only is that declaration unconstitutional, but building Trump’s desired border wall sends a bad signal to the neighbors of the United States to the south, according to House Speaker Nancy Pelosi.

Pelosi was with Rep. Henry Cuellar (D-Tex.) and Mayor Pete Saentz in Laredo, Texas, as part of a look at US border security ahead of House Democrats’ plan this week to pass a resolution of disapproval to stop Trump’s use of a “state of emergency” to bypass Congress, and essentially raid military funds to build his border wall.

The resolution is expected to pass the Democratic-controlled House easily.

Because it is a privileged resolution, Republican Senate Majority Leader Mitch McConnell will have no choice but to bring it to a vote. Sen. Susan Collins of Maine–who is potentially vulnerable when she is up for re-election next year–is the sole Senate Republican to commit to voting for the resolution of disapproval.

At least a handful of others is expected to join her. The question is whether enough Republicans desert Trump to override his expected veto of the legislation. Some 21 Republican votes would be required to override the veto, assuming all the Democrats vote for the resolution.

Democrats, and some Republicans, oppose Trump’s use of the emergency declaration on constitutional grounds. They argue that it violates the principle of separation of powers as well as usurping the congressional role of the power of the purse.

Pelosi, the top Democrat in the House, certainly supports the resolution of disapproval on those terms.

“This is about the oath we take to protect and defend the Constitution of the United States, our Founders very wisely placed in the Constitution provision for the separation of powers,” she said. “Co-equal branches of government, there to be, again, a check and balance on each other.”

But her opposition also is driven for the message that building the wall itself sends, Pelosi says.

“It’s clear that this is not an act of friendship,” she says. ” …We are all in one hemisphere. We are neighbors. Let’s be friends. Let’s respect each other in this hemisphere and I do know that many people in the Congress think that we should have more of a focus on our Latin American neighbors. Canada too, but also to the south of us – Mexico, Central America, and South America.

“So, let’s use this as a pivotal moment not only to uphold the Constitution, uphold our values and how we respect people, but use it as a moment to say, ‘Let’s go down a different path in terms of who we are as a hemisphere,” Pelosi adds. “We are all called Americans, North or South Americans.”

Correction: Henry Cuellar was incorrectly label as an Democrat. He is a Republican