Posts don’t display on blog page (it’s not the front page, which is static)

I created a static front page; it is where visitors land when they first arrive at the main URL, and can be returned to at any time via a HOME button on the horizontal menu. I also have a menu button for BLOG, which I want to take visitors to (naturally) the blog page. I seem to have made an error in how this is programmed, as no blog entries appear there. (They do show up on dynamically created pages when clicking categories or archives on the sidebar.) The only thing that appears on the BLOG page is the sidebar.

Here is what my code for that portion of the nav menu looks like in the header file:

<li><a <?php if (is_page('frontpage')) echo('class="current" '); ?>href="<?php bloginfo('url'); ?>/?page_id=28">home</a></li>

<li><a <?php if (is_home()) echo('class="current" '); ?>href="<?php bloginfo('url'); ?>/?page_id=1">blog</a></li>
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In the SETTINGS section of the dashboard, both “WordPress address” and “Blog address” are set to the primary URL. The “Reading Setting” for “Blog pages show at most” is set to 10.

Can anyone tell me what I am doing wrong, and what to change in order to have posts appear on the blog page?

Thank You!